New theme ui in user settings (#12576)

* Add hook to get the theme

* Adapt subsection settings to new ui

* WIP new theme subsection

* Add theme selection

* Fix test types

* Disabled theme selector when system theme is used

* Update compound to `4.4.1`

* Add custom theme support

* Remove old ThemChoicePanel

* Fix QuickThemeSwitcher-test.tsx

* Fix AppearanceUserSettingsTab-test.tsx

* Update i18n

* Fix ThemeChoicePanel-test.tsx

* Update `@vector-im/compound-web`

* Small tweaks

* Fix CSS comments and use compound variable

* Remove custom theme title

* i18n: update

* test: add tests to theme selection

* test: update AppearanceUserSettingsTab-test snapshot

* test: rework custom theme

* playwright: fix audio-player.spec.ts

* playwright: appearance tab

* test: update snapshot

* playright: add custom theme

* i18n: use correct char for ellipsis

* a11y: add missing aria-label to delete button

* dialog: update close button tooltip

* theme: remove local state and handle custom delete

* theme: don't add twice the same custom theme

* test: update snapshot

* playwright: update snapshot

* custom theme: add background to custom theme list

* update compound web

* Use new destructive property on `IconButton` of theme panel

* test: update snapshots

* rename new ui into legacy

* remove wrong constructor doc

* fix theme selector padding

* theme selector: fix key

* test: fix e2e

playwright/e2e/audio-player/audio-player.spec.ts

@@ -160,7 +160,7 @@ test.describe("Audio player", () => {
 
         // Enable high contrast manually
         const settings = await app.settings.openUserSettings("Appearance");
-        await settings.getByTestId("mx_ThemeChoicePanel").getByText("Use high contrast").click();
+        await settings.getByRole("radio", { name: "High contrast" }).click();
 
         await app.closeDialog();
 

playwright/e2e/settings/appearance-user-settings-tab/appearance-user-settings-tab.spec.ts

@@ -14,8 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { test, expect } from "../../element-web-test";
-import { SettingLevel } from "../../../src/settings/SettingLevel";
+import { expect, test } from ".";
 
 test.describe("Appearance user settings tab", () => {
     test.use({
@@ -151,69 +150,68 @@ test.describe("Appearance user settings tab", () => {
     });
 
     test.describe("Theme Choice Panel", () => {
-        test.beforeEach(async ({ app, user }) => {
+        test.beforeEach(async ({ app, user, util }) => {
             // Disable the default theme for consistency in case ThemeWatcher automatically chooses it
-            await app.settings.setValue("use_system_theme", null, SettingLevel.DEVICE, false);
+            await util.disableSystemTheme();
+            await util.openAppearanceTab();
         });
 
-        test("should be rendered with the light theme selected", async ({ page, app }) => {
-            await app.settings.openUserSettings("Appearance");
-            const themePanel = page.getByTestId("mx_ThemeChoicePanel");
-
-            const useSystemTheme = themePanel.getByTestId("checkbox-use-system-theme");
-            await expect(useSystemTheme.getByText("Match system theme")).toBeVisible();
+        test("should be rendered with the light theme selected", async ({ page, app, util }) => {
             // Assert that 'Match system theme' is not checked
-            // Note that mx_Checkbox_checkmark exists and is hidden by CSS if it is not checked
-            await expect(useSystemTheme.locator(".mx_Checkbox_checkmark")).not.toBeVisible();
+            await expect(util.getMatchSystemThemeCheckbox()).not.toBeChecked();
 
-            const selectors = themePanel.getByTestId("theme-choice-panel-selectors");
-            await expect(selectors.locator(".mx_ThemeSelector_light")).toBeVisible();
-            await expect(selectors.locator(".mx_ThemeSelector_dark")).toBeVisible();
             // Assert that the light theme is selected
-            await expect(selectors.locator(".mx_ThemeSelector_light.mx_StyledRadioButton_enabled")).toBeVisible();
-            // Assert that the buttons for the light and dark theme are not enabled
-            await expect(selectors.locator(".mx_ThemeSelector_light.mx_StyledRadioButton_disabled")).not.toBeVisible();
-            await expect(selectors.locator(".mx_ThemeSelector_dark.mx_StyledRadioButton_disabled")).not.toBeVisible();
+            await expect(util.getLightTheme()).toBeChecked();
+            // Assert that the dark and high contrast themes are not selected
+            await expect(util.getDarkTheme()).not.toBeChecked();
+            await expect(util.getHighContrastTheme()).not.toBeChecked();
 
-            // Assert that the checkbox for the high contrast theme is rendered
-            await expect(themePanel.locator(".mx_Checkbox", { hasText: "Use high contrast" })).toBeVisible();
+            await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-light.png");
         });
 
-        test("should disable the labels for themes and the checkbox for the high contrast theme if the checkbox for the system theme is clicked", async ({
-            page,
-            app,
-        }) => {
-            await app.settings.openUserSettings("Appearance");
-            const themePanel = page.getByTestId("mx_ThemeChoicePanel");
+        test("should disable the themes when the system theme is clicked", async ({ page, app, util }) => {
+            await util.getMatchSystemThemeCheckbox().click();
 
-            await themePanel.locator(".mx_Checkbox", { hasText: "Match system theme" }).click();
+            // Assert that the themes are disabled
+            await expect(util.getLightTheme()).toBeDisabled();
+            await expect(util.getDarkTheme()).toBeDisabled();
+            await expect(util.getHighContrastTheme()).toBeDisabled();
 
-            // Assert that the labels for the light theme and dark theme are disabled
-            await expect(themePanel.locator(".mx_ThemeSelector_light.mx_StyledRadioButton_disabled")).toBeVisible();
-            await expect(themePanel.locator(".mx_ThemeSelector_dark.mx_StyledRadioButton_disabled")).toBeVisible();
-
-            // Assert that there does not exist a label for an enabled theme
-            await expect(themePanel.locator("label.mx_StyledRadioButton_enabled")).not.toBeVisible();
-
-            // Assert that the checkbox and label to enable the high contrast theme should not exist
-            await expect(themePanel.locator(".mx_Checkbox", { hasText: "Use high contrast" })).not.toBeVisible();
+            await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-match-system-enabled.png");
         });
 
-        test("should not render the checkbox and the label for the high contrast theme if the dark theme is selected", async ({
-            page,
-            app,
-        }) => {
-            await app.settings.openUserSettings("Appearance");
-            const themePanel = page.getByTestId("mx_ThemeChoicePanel");
+        test("should change the theme to dark", async ({ page, app, util }) => {
+            // Assert that the light theme is selected
+            await expect(util.getLightTheme()).toBeChecked();
 
-            // Assert that the checkbox and the label to enable the high contrast theme should exist
-            await expect(themePanel.locator(".mx_Checkbox", { hasText: "Use high contrast" })).toBeVisible();
+            await util.getDarkTheme().click();
 
-            // Enable the dark theme
-            await themePanel.locator(".mx_ThemeSelector_dark").click();
+            // Assert that the light and high contrast themes are not selected
+            await expect(util.getLightTheme()).not.toBeChecked();
+            await expect(util.getDarkTheme()).toBeChecked();
+            await expect(util.getHighContrastTheme()).not.toBeChecked();
 
-            // Assert that the checkbox and the label should not exist
-            await expect(themePanel.locator(".mx_Checkbox", { hasText: "Use high contrast" })).not.toBeVisible();
+            await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-dark.png");
+        });
+
+        test.describe("custom theme", () => {
+            test.use({
+                labsFlags: ["feature_custom_themes"],
+            });
+
+            test("should render the custom theme section", async ({ page, app, util }) => {
+                await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-custom-theme.png");
+            });
+
+            test("should be able to add and remove a custom theme", async ({ page, app, util }) => {
+                await util.addCustomTheme();
+
+                await expect(util.getCustomTheme()).not.toBeChecked();
+                await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-custom-theme-added.png");
+
+                await util.removeCustomTheme();
+                await expect(util.getThemePanel()).toMatchScreenshot("theme-panel-custom-theme.png");
+            });
         });
     });
 });

playwright/e2e/settings/appearance-user-settings-tab/index.ts

@@ -0,0 +1,139 @@
+/*
+ * Copyright 2024 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Page } from "@playwright/test";
+
+import { ElementAppPage } from "../../../pages/ElementAppPage";
+import { test as base, expect } from "../../../element-web-test";
+import { SettingLevel } from "../../../../src/settings/SettingLevel";
+
+export { expect };
+
+/**
+ * Set up for the appearance tab test
+ */
+export const test = base.extend<{
+    util: Helpers;
+}>({
+    util: async ({ page, app }, use) => {
+        await use(new Helpers(page, app));
+    },
+});
+
+/**
+ * A collection of helper functions for the appearance tab test
+ * The goal is to make easier to get and interact with the button, input, or other elements of the appearance tab
+ */
+class Helpers {
+    private CUSTOM_THEME_URL = "http://custom.theme";
+    private CUSTOM_THEME = {
+        name: "Custom theme",
+        isDark: false,
+        colors: {},
+    };
+
+    constructor(
+        private page: Page,
+        private app: ElementAppPage,
+    ) {}
+
+    /**
+     * Open the appearance tab
+     */
+    openAppearanceTab() {
+        return this.app.settings.openUserSettings("Appearance");
+    }
+
+    // Theme Panel
+
+    /**
+     * Disable in the settings the system theme
+     */
+    disableSystemTheme() {
+        return this.app.settings.setValue("use_system_theme", null, SettingLevel.DEVICE, false);
+    }
+
+    /**
+     * Return the theme section
+     */
+    getThemePanel() {
+        return this.page.getByTestId("themePanel");
+    }
+
+    /**
+     * Return the system theme toggle
+     */
+    getMatchSystemThemeCheckbox() {
+        return this.getThemePanel().getByRole("checkbox");
+    }
+
+    /**
+     * Return the theme radio button
+     * @param theme - the theme to select
+     * @private
+     */
+    private getThemeRadio(theme: string) {
+        return this.getThemePanel().getByRole("radio", { name: theme });
+    }
+
+    /**
+     * Return the light theme radio button
+     */
+    getLightTheme() {
+        return this.getThemeRadio("Light");
+    }
+
+    /**
+     * Return the dark theme radio button
+     */
+    getDarkTheme() {
+        return this.getThemeRadio("Dark");
+    }
+
+    /**
+     * Return the custom theme radio button
+     */
+    getCustomTheme() {
+        return this.getThemeRadio(this.CUSTOM_THEME.name);
+    }
+
+    /**
+     * Return the high contrast theme radio button
+     */
+    getHighContrastTheme() {
+        return this.getThemeRadio("High contrast");
+    }
+
+    /**
+     * Add a custom theme
+     * Mock the request to the custom and return a fake local custom theme
+     */
+    async addCustomTheme() {
+        await this.page.route(this.CUSTOM_THEME_URL, (route) =>
+            route.fulfill({ body: JSON.stringify(this.CUSTOM_THEME) }),
+        );
+        await this.page.getByRole("textbox", { name: "Add custom theme" }).fill(this.CUSTOM_THEME_URL);
+        await this.page.getByRole("button", { name: "Add custom theme" }).click();
+        await this.page.unroute(this.CUSTOM_THEME_URL);
+    }
+
+    /**
+     * Remove the custom theme
+     */
+    removeCustomTheme() {
+        return this.getThemePanel().getByRole("listitem", { name: this.CUSTOM_THEME.name }).getByRole("button").click();
+    }
+}

res/css/_common.pcss

@@ -604,7 +604,7 @@ legend {
 .mx_Dialog
     button:not(.mx_Dialog_nonDialogButton):not([class|="maplibregl"]):not(.mx_AccessibleButton):not(
         .mx_UserProfileSettings button
-    ),
+    ):not(.mx_ThemeChoicePanel_CustomTheme button),
 .mx_Dialog input[type="submit"],
 .mx_Dialog_buttons button:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton),
 .mx_Dialog_buttons input[type="submit"] {
@@ -624,14 +624,14 @@ legend {
 .mx_Dialog
     button:not(.mx_Dialog_nonDialogButton):not([class|="maplibregl"]):not(.mx_AccessibleButton):not(
         .mx_UserProfileSettings button
-    ):last-child {
+    ):not(.mx_ThemeChoicePanel_CustomTheme button):last-child {
     margin-right: 0px;
 }
 
 .mx_Dialog
     button:not(.mx_Dialog_nonDialogButton):not([class|="maplibregl"]):not(.mx_AccessibleButton):not(
         .mx_UserProfileSettings button
-    ):focus,
+    ):not(.mx_ThemeChoicePanel_CustomTheme button):focus,
 .mx_Dialog input[type="submit"]:focus,
 .mx_Dialog_buttons button:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton):focus,
 .mx_Dialog_buttons input[type="submit"]:focus {
@@ -643,7 +643,7 @@ legend {
 .mx_Dialog_buttons
     button.mx_Dialog_primary:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton):not(
         .mx_UserProfileSettings button
-    ),
+    ):not(.mx_ThemeChoicePanel_CustomTheme button),
 .mx_Dialog_buttons input[type="submit"].mx_Dialog_primary {
     color: var(--cpd-color-text-on-solid-primary);
     background-color: var(--cpd-color-bg-action-primary-rest);
@@ -654,7 +654,9 @@ legend {
 .mx_Dialog button.danger:not(.mx_Dialog_nonDialogButton):not([class|="maplibregl"]),
 .mx_Dialog input[type="submit"].danger,
 .mx_Dialog_buttons
-    button.danger:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton):not(.mx_UserProfileSettings button),
+    button.danger:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton):not(.mx_UserProfileSettings button):not(
+        .mx_ThemeChoicePanel_CustomTheme button
+    ),
 .mx_Dialog_buttons input[type="submit"].danger {
     background-color: var(--cpd-color-bg-critical-primary);
     border: solid 1px var(--cpd-color-bg-critical-primary);
@@ -670,7 +672,7 @@ legend {
 .mx_Dialog
     button:not(.mx_Dialog_nonDialogButton):not([class|="maplibregl"]):not(.mx_AccessibleButton):not(
         .mx_UserProfileSettings button
-    ):disabled,
+    ):not(.mx_ThemeChoicePanel_CustomTheme button):disabled,
 .mx_Dialog input[type="submit"]:disabled,
 .mx_Dialog_buttons button:not(.mx_Dialog_nonDialogButton):not(.mx_AccessibleButton):disabled,
 .mx_Dialog_buttons input[type="submit"]:disabled {

res/css/components/views/settings/shared/_SettingsSubsection.pcss

@@ -17,6 +17,12 @@ limitations under the License.
 .mx_SettingsSubsection {
     width: 100%;
     box-sizing: border-box;
+
+    &.mx_SettingsSubsection_newUi {
+        display: flex;
+        flex-direction: column;
+        gap: var(--cpd-space-8x);
+    }
 }
 
 .mx_SettingsSubsection_description {
@@ -54,4 +60,8 @@ limitations under the License.
     &.mx_SettingsSubsection_noHeading {
         margin-top: 0;
     }
+    &.mx_SettingsSubsection_content_newUi {
+        gap: var(--cpd-space-6x);
+        margin-top: 0;
+    }
 }

res/css/views/settings/_ThemeChoicePanel.pcss

@@ -14,48 +14,72 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-.mx_ThemeChoicePanel_themeSelectors {
-    color: $primary-content;
+.mx_ThemeChoicePanel_ThemeSelectors {
     display: flex;
-    flex-direction: row;
     flex-wrap: wrap;
+    /* Override form default style */
+    flex-direction: row !important;
+    gap: var(--cpd-space-4x) !important;
 
-    > .mx_StyledRadioButton {
-        align-items: center;
-        padding: $font-16px;
-        box-sizing: border-box;
-        border-radius: 10px;
-        width: 180px;
+    .mx_ThemeChoicePanel_themeSelector {
+        border: 1px solid var(--cpd-color-border-interactive-secondary);
+        border-radius: var(--cpd-space-1-5x);
+        padding: var(--cpd-space-3x) var(--cpd-space-5x) var(--cpd-space-3x) var(--cpd-space-3x);
+        gap: var(--cpd-space-2x);
+        background-color: var(--cpd-color-bg-canvas-default);
 
-        background: $accent-200;
-        opacity: 0.4;
-
-        flex-shrink: 1;
-        flex-grow: 0;
-
-        margin-right: 15px;
-        margin-top: 10px;
-
-        font-weight: var(--cpd-font-weight-semibold);
-
-        > span {
-            justify-content: center;
-        }
-    }
-
-    > .mx_StyledRadioButton_enabled {
-        opacity: 1;
-
-        /* These colors need to be hardcoded because they don't change with the theme */
-        &.mx_ThemeSelector_light {
-            background-color: #f3f8fd;
-            color: #2e2f32;
+        &.mx_ThemeChoicePanel_themeSelector_enabled {
+            border-color: var(--cpd-color-border-interactive-primary);
         }
 
-        &.mx_ThemeSelector_dark {
-            /* 5% lightened version of 181b21 */
-            background-color: #25282e;
-            color: #f3f8fd;
+        &.mx_ThemeChoicePanel_themeSelector_disabled {
+            border-color: var(--cpd-color-border-disabled);
+        }
+
+        .mx_ThemeChoicePanel_themeSelector_Label {
+            color: var(--cpd-color-text-primary);
+            font: var(--cpd-font-body-md-semibold);
+        }
+    }
+}
+
+.mx_ThemeChoicePanel_CustomTheme {
+    width: 100%;
+    display: flex;
+    flex-direction: column;
+    gap: var(--cpd-space-4x);
+
+    .mx_ThemeChoicePanel_CustomTheme_EditInPlace input:focus {
+        /*
+         * When the input is focused, the border is growing
+         * We need to move it a bit to avoid the left border to be under the left panel
+         */
+        margin-left: var(--cpd-space-0-5x);
+    }
+
+    .mx_ThemeChoicePanel_CustomThemeList {
+        display: flex;
+        flex-direction: column;
+        gap: var(--cpd-space-4x);
+        /*
+         * Override the default padding/margin of the list
+         */
+        padding: 0;
+        margin: 0;
+
+        .mx_ThemeChoicePanel_CustomThemeList_theme {
+            display: flex;
+            justify-content: space-between;
+            align-items: center;
+            background-color: var(--cpd-color-gray-200);
+            padding: var(--cpd-space-2x) var(--cpd-space-2x) var(--cpd-space-2x) var(--cpd-space-4x);
+
+            .mx_ThemeChoicePanel_CustomThemeList_name {
+                font: var(--cpd-font-body-sm-semibold);
+                overflow: hidden;
+                text-overflow: ellipsis;
+                white-space: nowrap;
+            }
         }
     }
 }

src/components/views/dialogs/BaseDialog.tsx

@@ -128,7 +128,8 @@ export default class BaseDialog extends React.Component<IProps> {
                     onClick={this.onCancelClick}
                     className="mx_Dialog_cancelButton"
                     aria-label={_t("dialog_close_label")}
-                    title={_t("dialog_close_label")}
+                    title={_t("action|close")}
+                    placement="bottom"
                 />
             );
         }

src/components/views/settings/ThemeChoicePanel.tsx

@@ -1,285 +1,340 @@
 /*
-Copyright 2021 The Matrix.org Foundation C.I.C.
+ * Copyright 2024 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-import React from "react";
+import React, { ChangeEvent, JSX, useCallback, useMemo, useRef, useState } from "react";
+import {
+    InlineField,
+    ToggleControl,
+    Label,
+    Root,
+    RadioControl,
+    EditInPlace,
+    IconButton,
+} from "@vector-im/compound-web";
+import { Icon as DeleteIcon } from "@vector-im/compound-design-tokens/icons/delete.svg";
+import classNames from "classnames";
 import { logger } from "matrix-js-sdk/src/logger";
 
 import { _t } from "../../../languageHandler";
-import SettingsStore from "../../../settings/SettingsStore";
-import { findHighContrastTheme, findNonHighContrastTheme, getOrderedThemes, isHighContrastTheme } from "../../../theme";
+import SettingsSubsection from "./shared/SettingsSubsection";
 import ThemeWatcher from "../../../settings/watchers/ThemeWatcher";
-import AccessibleButton from "../elements/AccessibleButton";
+import SettingsStore from "../../../settings/SettingsStore";
+import { SettingLevel } from "../../../settings/SettingLevel";
 import dis from "../../../dispatcher/dispatcher";
 import { RecheckThemePayload } from "../../../dispatcher/payloads/RecheckThemePayload";
 import { Action } from "../../../dispatcher/actions";
-import StyledCheckbox from "../elements/StyledCheckbox";
-import Field from "../elements/Field";
-import StyledRadioGroup from "../elements/StyledRadioGroup";
-import { SettingLevel } from "../../../settings/SettingLevel";
-import PosthogTrackers from "../../../PosthogTrackers";
-import SettingsSubsection from "./shared/SettingsSubsection";
+import { useTheme } from "../../../hooks/useTheme";
+import { findHighContrastTheme, getOrderedThemes, CustomTheme as CustomThemeType, ITheme } from "../../../theme";
+import { useSettingValue } from "../../../hooks/useSettings";
 
-interface IProps {}
+/**
+ * Panel to choose the theme
+ */
+export function ThemeChoicePanel(): JSX.Element {
+    const themeState = useTheme();
+    const themeWatcher = useRef(new ThemeWatcher());
+    const customThemeEnabled = useSettingValue<boolean>("feature_custom_themes");
 
-interface IThemeState {
+    return (
+        <SettingsSubsection heading={_t("common|theme")} legacy={false} data-testid="themePanel">
+            {themeWatcher.current.isSystemThemeSupported() && (
+                <SystemTheme systemThemeActivated={themeState.systemThemeActivated} />
+            )}
+            <ThemeSelectors theme={themeState.theme} disabled={themeState.systemThemeActivated} />
+            {customThemeEnabled && <CustomTheme theme={themeState.theme} />}
+        </SettingsSubsection>
+    );
+}
+
+/**
+ * Component to toggle the system theme
+ */
+interface SystemThemeProps {
+    /* Whether the system theme is activated */
+    systemThemeActivated: boolean;
+}
+
+/**
+ * Component to toggle the system theme
+ */
+function SystemTheme({ systemThemeActivated }: SystemThemeProps): JSX.Element {
+    return (
+        <Root
+            onChange={async (evt) => {
+                const checked = new FormData(evt.currentTarget).get("systemTheme") === "on";
+                await SettingsStore.setValue("use_system_theme", null, SettingLevel.DEVICE, checked);
+                dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme });
+            }}
+        >
+            <InlineField
+                name="systemTheme"
+                control={<ToggleControl name="systemTheme" defaultChecked={systemThemeActivated} />}
+            >
+                <Label>{SettingsStore.getDisplayName("use_system_theme")}</Label>
+            </InlineField>
+        </Root>
+    );
+}
+
+/**
+ * Component to select the theme
+ */
+interface ThemeSelectorProps {
+    /* The current theme */
     theme: string;
-    useSystemTheme: boolean;
+    /* The theme can't be selected */
+    disabled: boolean;
 }
 
-export interface CustomThemeMessage {
-    isError: boolean;
-    text: string;
-}
+/**
+ * Component to select the theme
+ */
+function ThemeSelectors({ theme, disabled }: ThemeSelectorProps): JSX.Element {
+    const themes = useThemes();
 
-interface IState extends IThemeState {
-    customThemeUrl: string;
-    customThemeMessage: CustomThemeMessage;
-}
+    return (
+        <Root
+            className="mx_ThemeChoicePanel_ThemeSelectors"
+            onChange={async (evt) => {
+                // We don't have any file in the form, we can cast it as string safely
+                const newTheme = new FormData(evt.currentTarget).get("themeSelector") as string | null;
 
-export default class ThemeChoicePanel extends React.Component<IProps, IState> {
-    private themeTimer?: number;
+                // Do nothing if the same theme is selected
+                if (!newTheme || theme === newTheme) return;
 
-    public constructor(props: IProps) {
-        super(props);
-
-        this.state = {
-            ...ThemeChoicePanel.calculateThemeState(),
-            customThemeUrl: "",
-            customThemeMessage: { isError: false, text: "" },
-        };
-    }
-
-    public static calculateThemeState(): IThemeState {
-        // We have to mirror the logic from ThemeWatcher.getEffectiveTheme so we
-        // show the right values for things.
-
-        const themeChoice: string = SettingsStore.getValue("theme");
-        const systemThemeExplicit: boolean = SettingsStore.getValueAt(
-            SettingLevel.DEVICE,
-            "use_system_theme",
-            null,
-            false,
-            true,
-        );
-        const themeExplicit: string = SettingsStore.getValueAt(SettingLevel.DEVICE, "theme", null, false, true);
-
-        // If the user has enabled system theme matching, use that.
-        if (systemThemeExplicit) {
-            return {
-                theme: themeChoice,
-                useSystemTheme: true,
-            };
-        }
-
-        // If the user has set a theme explicitly, use that (no system theme matching)
-        if (themeExplicit) {
-            return {
-                theme: themeChoice,
-                useSystemTheme: false,
-            };
-        }
-
-        // Otherwise assume the defaults for the settings
-        return {
-            theme: themeChoice,
-            useSystemTheme: SettingsStore.getValueAt(SettingLevel.DEVICE, "use_system_theme"),
-        };
-    }
-
-    private onThemeChange = (newTheme: string): void => {
-        if (this.state.theme === newTheme) return;
-
-        PosthogTrackers.trackInteraction("WebSettingsAppearanceTabThemeSelector");
-
-        // doing getValue in the .catch will still return the value we failed to set,
-        // so remember what the value was before we tried to set it so we can revert
-        const oldTheme: string = SettingsStore.getValue("theme");
-        SettingsStore.setValue("theme", null, SettingLevel.DEVICE, newTheme).catch(() => {
-            dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme });
-            this.setState({ theme: oldTheme });
-        });
-        this.setState({ theme: newTheme });
-        // The settings watcher doesn't fire until the echo comes back from the
-        // server, so to make the theme change immediately we need to manually
-        // do the dispatch now
-        // XXX: The local echoed value appears to be unreliable, in particular
-        // when settings custom themes(!) so adding forceTheme to override
-        // the value from settings.
-        dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme, forceTheme: newTheme });
-    };
-
-    private onUseSystemThemeChanged = (checked: boolean): void => {
-        this.setState({ useSystemTheme: checked });
-        SettingsStore.setValue("use_system_theme", null, SettingLevel.DEVICE, checked);
-        dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme });
-    };
-
-    private onAddCustomTheme = async (): Promise<void> => {
-        let currentThemes: string[] = SettingsStore.getValue("custom_themes");
-        if (!currentThemes) currentThemes = [];
-        currentThemes = currentThemes.map((c) => c); // cheap clone
-
-        if (this.themeTimer) {
-            clearTimeout(this.themeTimer);
-        }
-
-        try {
-            const r = await fetch(this.state.customThemeUrl);
-            // XXX: need some schema for this
-            const themeInfo = await r.json();
-            if (!themeInfo || typeof themeInfo["name"] !== "string" || typeof themeInfo["colors"] !== "object") {
-                this.setState({
-                    customThemeMessage: { text: _t("settings|appearance|custom_theme_invalid"), isError: true },
+                // doing getValue in the .catch will still return the value we failed to set,
+                SettingsStore.setValue("theme", null, SettingLevel.DEVICE, newTheme).catch(() => {
+                    dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme });
                 });
-                return;
-            }
-            currentThemes.push(themeInfo);
-        } catch (e) {
-            logger.error(e);
-            this.setState({
-                customThemeMessage: { text: _t("settings|appearance|custom_theme_error_downloading"), isError: true },
-            });
-            return; // Don't continue on error
-        }
 
-        await SettingsStore.setValue("custom_themes", null, SettingLevel.ACCOUNT, currentThemes);
-        this.setState({
-            customThemeUrl: "",
-            customThemeMessage: { text: _t("settings|appearance|custom_theme_success"), isError: false },
-        });
-
-        this.themeTimer = window.setTimeout(() => {
-            this.setState({ customThemeMessage: { text: "", isError: false } });
-        }, 3000);
-    };
-
-    private onCustomThemeChange = (e: React.ChangeEvent<HTMLSelectElement | HTMLInputElement>): void => {
-        this.setState({ customThemeUrl: e.target.value });
-    };
-
-    private renderHighContrastCheckbox(): React.ReactElement<HTMLDivElement> | undefined {
-        if (
-            !this.state.useSystemTheme &&
-            (findHighContrastTheme(this.state.theme) || isHighContrastTheme(this.state.theme))
-        ) {
-            return (
-                <div>
-                    <StyledCheckbox
-                        checked={isHighContrastTheme(this.state.theme)}
-                        onChange={(e) => this.highContrastThemeChanged(e.target.checked)}
+                // The settings watcher doesn't fire until the echo comes back from the
+                // server, so to make the theme change immediately we need to manually
+                // do the dispatch now
+                // XXX: The local echoed value appears to be unreliable, in particular
+                // when settings custom themes(!) so adding forceTheme to override
+                // the value from settings.
+                dis.dispatch<RecheckThemePayload>({ action: Action.RecheckTheme, forceTheme: newTheme });
+            }}
+        >
+            {themes.map((_theme) => {
+                const isChecked = theme === _theme.id;
+                return (
+                    <InlineField
+                        className={classNames("mx_ThemeChoicePanel_themeSelector", {
+                            [`mx_ThemeChoicePanel_themeSelector_enabled`]: !disabled && theme === _theme.id,
+                            [`mx_ThemeChoicePanel_themeSelector_disabled`]: disabled,
+                            // We need to force the compound theme to be light or dark
+                            // The theme selection doesn't depend on the current theme
+                            // For example when the light theme is used, the dark theme selector should be dark
+                            "cpd-theme-light": !_theme.isDark,
+                            "cpd-theme-dark": _theme.isDark,
+                        })}
+                        name="themeSelector"
+                        key={_theme.id}
+                        control={
+                            <RadioControl
+                                name="themeSelector"
+                                checked={!disabled && isChecked}
+                                disabled={disabled}
+                                value={_theme.id}
+                            />
+                        }
                     >
-                        {_t("settings|appearance|use_high_contrast")}
-                    </StyledCheckbox>
-                </div>
-            );
-        }
-    }
+                        <Label className="mx_ThemeChoicePanel_themeSelector_Label">{_theme.name}</Label>
+                    </InlineField>
+                );
+            })}
+        </Root>
+    );
+}
 
-    private highContrastThemeChanged(checked: boolean): void {
-        let newTheme: string | undefined;
-        if (checked) {
-            newTheme = findHighContrastTheme(this.state.theme);
-        } else {
-            newTheme = findNonHighContrastTheme(this.state.theme);
-        }
-        if (newTheme) {
-            this.onThemeChange(newTheme);
-        }
-    }
-
-    public render(): React.ReactElement<HTMLDivElement> {
-        const themeWatcher = new ThemeWatcher();
-        let systemThemeSection: JSX.Element | undefined;
-        if (themeWatcher.isSystemThemeSupported()) {
-            systemThemeSection = (
-                <div data-testid="checkbox-use-system-theme">
-                    <StyledCheckbox
-                        checked={this.state.useSystemTheme}
-                        onChange={(e) => this.onUseSystemThemeChanged(e.target.checked)}
-                    >
-                        {SettingsStore.getDisplayName("use_system_theme")}
-                    </StyledCheckbox>
-                </div>
-            );
-        }
-
-        let customThemeForm: JSX.Element | undefined;
-        if (SettingsStore.getValue("feature_custom_themes")) {
-            let messageElement: JSX.Element | undefined;
-            if (this.state.customThemeMessage.text) {
-                if (this.state.customThemeMessage.isError) {
-                    messageElement = <div className="text-error">{this.state.customThemeMessage.text}</div>;
-                } else {
-                    messageElement = <div className="text-success">{this.state.customThemeMessage.text}</div>;
-                }
-            }
-            customThemeForm = (
-                <div className="mx_SettingsTab_section">
-                    <form onSubmit={this.onAddCustomTheme}>
-                        <Field
-                            label={_t("settings|appearance|custom_theme_url")}
-                            type="text"
-                            id="mx_GeneralUserSettingsTab_customThemeInput"
-                            autoComplete="off"
-                            onChange={this.onCustomThemeChange}
-                            value={this.state.customThemeUrl}
-                        />
-                        <AccessibleButton
-                            onClick={this.onAddCustomTheme}
-                            type="submit"
-                            kind="primary_sm"
-                            disabled={!this.state.customThemeUrl.trim()}
-                        >
-                            {_t("settings|appearance|custom_theme_add_button")}
-                        </AccessibleButton>
-                        {messageElement}
-                    </form>
-                </div>
-            );
-        }
-
-        const orderedThemes = getOrderedThemes();
-        return (
-            <SettingsSubsection heading={_t("common|theme")} data-testid="mx_ThemeChoicePanel">
-                {systemThemeSection}
-                <div className="mx_ThemeChoicePanel_themeSelectors" data-testid="theme-choice-panel-selectors">
-                    <StyledRadioGroup
-                        name="theme"
-                        definitions={orderedThemes.map((t) => ({
-                            value: t.id,
-                            label: t.name,
-                            disabled: this.state.useSystemTheme,
-                            className: "mx_ThemeSelector_" + t.id,
-                        }))}
-                        onChange={this.onThemeChange}
-                        value={this.apparentSelectedThemeId()}
-                        outlined
-                    />
-                </div>
-                {this.renderHighContrastCheckbox()}
-                {customThemeForm}
-            </SettingsSubsection>
+/**
+ * Return all the available themes
+ */
+function useThemes(): Array<ITheme & { isDark: boolean }> {
+    const customThemes = useSettingValue<CustomThemeType[] | undefined>("custom_themes");
+    return useMemo(() => {
+        // Put the custom theme into a map
+        // To easily find the theme by name when going through the themes list
+        const checkedCustomThemes = customThemes || [];
+        const customThemeMap = checkedCustomThemes.reduce(
+            (map, theme) => map.set(theme.name, theme),
+            new Map<string, CustomThemeType>(),
         );
-    }
 
-    public apparentSelectedThemeId(): string | undefined {
-        if (this.state.useSystemTheme) {
-            return undefined;
-        }
-        const nonHighContrast = findNonHighContrastTheme(this.state.theme);
-        return nonHighContrast ? nonHighContrast : this.state.theme;
+        const themes = getOrderedThemes();
+        // Separate the built-in themes from the custom themes
+        // To insert the high contrast theme between them
+        const builtInThemes = themes.filter((theme) => !customThemeMap.has(theme.name));
+        const otherThemes = themes.filter((theme) => customThemeMap.has(theme.name));
+
+        const highContrastTheme = makeHighContrastTheme();
+        if (highContrastTheme) builtInThemes.push(highContrastTheme);
+
+        const allThemes = builtInThemes.concat(otherThemes);
+
+        // Check if the themes are dark
+        return allThemes.map((theme) => {
+            const customTheme = customThemeMap.get(theme.name);
+            const isDark = (customTheme ? customTheme.is_dark : theme.id.includes("dark")) || false;
+            return { ...theme, isDark };
+        });
+    }, [customThemes]);
+}
+
+/**
+ * Create the light high contrast theme
+ */
+function makeHighContrastTheme(): ITheme | undefined {
+    const lightHighContrastId = findHighContrastTheme("light");
+    if (lightHighContrastId) {
+        return {
+            name: _t("settings|appearance|high_contrast"),
+            id: lightHighContrastId,
+        };
     }
 }
+
+interface CustomThemeProps {
+    /**
+     * The current theme
+     */
+    theme: string;
+}
+
+/**
+ * Add and manager custom themes
+ */
+function CustomTheme({ theme }: CustomThemeProps): JSX.Element {
+    const [customTheme, setCustomTheme] = useState<string>("");
+    const [error, setError] = useState<string>();
+    const clear = useCallback(() => {
+        setError(undefined);
+        setCustomTheme("");
+    }, [setError, setCustomTheme]);
+
+    return (
+        <div className="mx_ThemeChoicePanel_CustomTheme">
+            <EditInPlace
+                className="mx_ThemeChoicePanel_CustomTheme_EditInPlace"
+                label={_t("settings|appearance|custom_theme_add")}
+                saveButtonLabel={_t("settings|appearance|custom_theme_add")}
+                savingLabel={_t("settings|appearance|custom_theme_downloading")}
+                helpLabel={_t("settings|appearance|custom_theme_help")}
+                error={error}
+                value={customTheme}
+                onChange={(e: ChangeEvent<HTMLInputElement>) => {
+                    setError(undefined);
+                    setCustomTheme(e.target.value);
+                }}
+                onSave={async () => {
+                    // The field empty is empty
+                    if (!customTheme) return;
+
+                    // Get the custom themes and do a cheap clone
+                    // To avoid to mutate the original array in the settings
+                    const currentThemes =
+                        SettingsStore.getValue<CustomThemeType[]>("custom_themes").map((t) => t) || [];
+
+                    try {
+                        const r = await fetch(customTheme);
+                        // XXX: need some schema for this
+                        const themeInfo = await r.json();
+                        if (
+                            !themeInfo ||
+                            typeof themeInfo["name"] !== "string" ||
+                            typeof themeInfo["colors"] !== "object"
+                        ) {
+                            setError(_t("settings|appearance|custom_theme_invalid"));
+                            return;
+                        }
+
+                        // Check if the theme is already existing
+                        const isAlreadyExisting = Boolean(currentThemes.find((t) => t.name === themeInfo.name));
+                        if (isAlreadyExisting) {
+                            clear();
+                            return;
+                        }
+
+                        currentThemes.push(themeInfo);
+                    } catch (e) {
+                        logger.error(e);
+                        setError(_t("settings|appearance|custom_theme_error_downloading"));
+                        return;
+                    }
+
+                    // Reset the error
+                    clear();
+                    await SettingsStore.setValue("custom_themes", null, SettingLevel.ACCOUNT, currentThemes);
+                }}
+                onCancel={clear}
+            />
+            <CustomThemeList theme={theme} />
+        </div>
+    );
+}
+
+interface CustomThemeListProps {
+    /*
+     * The current theme
+     */
+    theme: string;
+}
+
+/**
+ * List of the custom themes
+ */
+function CustomThemeList({ theme: currentTheme }: CustomThemeListProps): JSX.Element {
+    const customThemes = useSettingValue<CustomThemeType[]>("custom_themes") || [];
+
+    return (
+        <ul className="mx_ThemeChoicePanel_CustomThemeList">
+            {customThemes.map((theme) => {
+                return (
+                    <li key={theme.name} className="mx_ThemeChoicePanel_CustomThemeList_theme" aria-label={theme.name}>
+                        <span className="mx_ThemeChoicePanel_CustomThemeList_name">{theme.name}</span>
+                        <IconButton
+                            destructive={true}
+                            aria-label={_t("action|delete")}
+                            tooltip={_t("action|delete")}
+                            onClick={async () => {
+                                // Get the custom themes and do a cheap clone
+                                // To avoid to mutate the original array in the settings
+                                const currentThemes =
+                                    SettingsStore.getValue<CustomThemeType[]>("custom_themes").map((t) => t) || [];
+
+                                // Remove the theme from the list
+                                const newThemes = currentThemes.filter((t) => t.name !== theme.name);
+                                await SettingsStore.setValue("custom_themes", null, SettingLevel.ACCOUNT, newThemes);
+
+                                // If the delete custom theme is the current theme, reset the theme to the default theme
+                                // By settings the theme at null at the device level, we are getting the default theme
+                                if (currentTheme === `custom-${theme.name}`) {
+                                    await SettingsStore.setValue("theme", null, SettingLevel.DEVICE, null);
+                                    dis.dispatch<RecheckThemePayload>({
+                                        action: Action.RecheckTheme,
+                                    });
+                                }
+                            }}
+                        >
+                            <DeleteIcon />
+                        </IconButton>
+                    </li>
+                );
+            })}
+        </ul>
+    );
+}

src/components/views/settings/shared/SettingsSubsection.tsx

@@ -16,6 +16,7 @@ limitations under the License.
 
 import classNames from "classnames";
 import React, { HTMLAttributes } from "react";
+import { Separator } from "@vector-im/compound-web";
 
 import { SettingsSubsectionHeading } from "./SettingsSubsectionHeading";
 
@@ -25,6 +26,11 @@ export interface SettingsSubsectionProps extends HTMLAttributes<HTMLDivElement>
     children?: React.ReactNode;
     // when true content will be justify-items: stretch, which will make items within the section stretch to full width.
     stretchContent?: boolean;
+    /*
+     * When true, the legacy UI style will be applied to the subsection.
+     * @default true
+     */
+    legacy?: boolean;
 }
 
 export const SettingsSubsectionText: React.FC<HTMLAttributes<HTMLDivElement>> = ({ children, ...rest }) => (
@@ -38,10 +44,16 @@ export const SettingsSubsection: React.FC<SettingsSubsectionProps> = ({
     description,
     children,
     stretchContent,
+    legacy = true,
     ...rest
 }) => (
-    <div {...rest} className="mx_SettingsSubsection">
-        {typeof heading === "string" ? <SettingsSubsectionHeading heading={heading} /> : <>{heading}</>}
+    <div
+        {...rest}
+        className={classNames("mx_SettingsSubsection", {
+            mx_SettingsSubsection_newUi: !legacy,
+        })}
+    >
+        {typeof heading === "string" ? <SettingsSubsectionHeading heading={heading} legacy={legacy} /> : <>{heading}</>}
         {!!description && (
             <div className="mx_SettingsSubsection_description">
                 <SettingsSubsectionText>{description}</SettingsSubsectionText>
@@ -52,11 +64,13 @@ export const SettingsSubsection: React.FC<SettingsSubsectionProps> = ({
                 className={classNames("mx_SettingsSubsection_content", {
                     mx_SettingsSubsection_contentStretch: !!stretchContent,
                     mx_SettingsSubsection_noHeading: !heading && !description,
+                    mx_SettingsSubsection_content_newUi: !legacy,
                 })}
             >
                 {children}
             </div>
         )}
+        {!legacy && <Separator />}
     </div>
 );
 

src/components/views/settings/shared/SettingsSubsectionHeading.tsx

@@ -20,14 +20,24 @@ import Heading from "../../typography/Heading";
 
 export interface SettingsSubsectionHeadingProps extends HTMLAttributes<HTMLDivElement> {
     heading: string;
+    legacy?: boolean;
     children?: React.ReactNode;
 }
 
-export const SettingsSubsectionHeading: React.FC<SettingsSubsectionHeadingProps> = ({ heading, children, ...rest }) => (
-    <div {...rest} className="mx_SettingsSubsectionHeading">
-        <Heading className="mx_SettingsSubsectionHeading_heading" size="4" as="h3">
-            {heading}
-        </Heading>
-        {children}
-    </div>
-);
+export const SettingsSubsectionHeading: React.FC<SettingsSubsectionHeadingProps> = ({
+    heading,
+    legacy = true,
+    children,
+    ...rest
+}) => {
+    const size = legacy ? "4" : "3";
+
+    return (
+        <div {...rest} className="mx_SettingsSubsectionHeading">
+            <Heading className="mx_SettingsSubsectionHeading_heading" size={size} as="h3">
+                {heading}
+            </Heading>
+            {children}
+        </div>
+    );
+};

src/components/views/settings/tabs/user/AppearanceUserSettingsTab.tsx

@@ -28,7 +28,7 @@ import { UIFeature } from "../../../../../settings/UIFeature";
 import { Layout } from "../../../../../settings/enums/Layout";
 import LayoutSwitcher from "../../LayoutSwitcher";
 import FontScalingPanel from "../../FontScalingPanel";
-import ThemeChoicePanel from "../../ThemeChoicePanel";
+import { ThemeChoicePanel } from "../../ThemeChoicePanel";
 import ImageSizePanel from "../../ImageSizePanel";
 import SettingsTab from "../SettingsTab";
 import { SettingsSection } from "../../shared/SettingsSection";

src/components/views/spaces/QuickThemeSwitcher.tsx

@@ -20,13 +20,13 @@ import { _t } from "../../../languageHandler";
 import { Action } from "../../../dispatcher/actions";
 import { findNonHighContrastTheme, getOrderedThemes } from "../../../theme";
 import Dropdown from "../elements/Dropdown";
-import ThemeChoicePanel from "../settings/ThemeChoicePanel";
 import SettingsStore from "../../../settings/SettingsStore";
 import { SettingLevel } from "../../../settings/SettingLevel";
 import dis from "../../../dispatcher/dispatcher";
 import { RecheckThemePayload } from "../../../dispatcher/payloads/RecheckThemePayload";
 import PosthogTrackers from "../../../PosthogTrackers";
 import { NonEmptyArray } from "../../../@types/common";
+import { useTheme } from "../../../hooks/useTheme";
 
 type Props = {
     requestClose: () => void;
@@ -37,10 +37,10 @@ const MATCH_SYSTEM_THEME_ID = "MATCH_SYSTEM_THEME_ID";
 const QuickThemeSwitcher: React.FC<Props> = ({ requestClose }) => {
     const orderedThemes = useMemo(getOrderedThemes, []);
 
-    const themeState = ThemeChoicePanel.calculateThemeState();
+    const themeState = useTheme();
     const nonHighContrast = findNonHighContrastTheme(themeState.theme);
     const theme = nonHighContrast ? nonHighContrast : themeState.theme;
-    const { useSystemTheme } = themeState;
+    const { systemThemeActivated } = themeState;
 
     const themeOptions = [
         {
@@ -50,7 +50,7 @@ const QuickThemeSwitcher: React.FC<Props> = ({ requestClose }) => {
         ...orderedThemes,
     ];
 
-    const selectedTheme = useSystemTheme ? MATCH_SYSTEM_THEME_ID : theme;
+    const selectedTheme = systemThemeActivated ? MATCH_SYSTEM_THEME_ID : theme;
 
     const onOptionChange = async (newTheme: string): Promise<void> => {
         PosthogTrackers.trackInteraction("WebQuickSettingsThemeDropdown");

src/hooks/useSettings.ts

@@ -17,6 +17,7 @@ limitations under the License.
 import { useEffect, useState } from "react";
 
 import SettingsStore from "../settings/SettingsStore";
+import { SettingLevel } from "../settings/SettingLevel";
 
 // Hook to fetch the value of a setting and dynamically update when it changes
 export const useSettingValue = <T>(settingName: string, roomId: string | null = null, excludeDefault = false): T => {
@@ -35,6 +36,39 @@ export const useSettingValue = <T>(settingName: string, roomId: string | null =
     return value;
 };
 
+/**
+ * Hook to fetch the value of a setting at a specific level and dynamically update when it changes
+ * @see SettingsStore.getValueAt
+ * @param level
+ * @param settingName
+ * @param roomId
+ * @param explicit
+ * @param excludeDefault
+ */
+export const useSettingValueAt = <T>(
+    level: SettingLevel,
+    settingName: string,
+    roomId: string | null = null,
+    explicit = false,
+    excludeDefault = false,
+): T => {
+    const [value, setValue] = useState(
+        SettingsStore.getValueAt<T>(level, settingName, roomId, explicit, excludeDefault),
+    );
+
+    useEffect(() => {
+        const ref = SettingsStore.watchSetting(settingName, roomId, () => {
+            setValue(SettingsStore.getValueAt<T>(level, settingName, roomId, explicit, excludeDefault));
+        });
+        // clean-up
+        return () => {
+            SettingsStore.unwatchSetting(ref);
+        };
+    }, [level, settingName, roomId, explicit, excludeDefault]);
+
+    return value;
+};
+
 // Hook to fetch whether a feature is enabled and dynamically update when that changes
 export const useFeatureEnabled = (featureName: string, roomId: string | null = null): boolean => {
     const [enabled, setEnabled] = useState(SettingsStore.getValue<boolean>(featureName, roomId));

src/hooks/useTheme.ts

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2024 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { SettingLevel } from "../settings/SettingLevel";
+import { useSettingValue, useSettingValueAt } from "./useSettings";
+
+/**
+ * Hook to fetch the current theme and whether system theme matching is enabled.
+ */
+export function useTheme(): { theme: string; systemThemeActivated: boolean } {
+    // We have to mirror the logic from ThemeWatcher.getEffectiveTheme so we
+    // show the right values for things.
+
+    const themeChoice = useSettingValue<string>("theme");
+    const systemThemeExplicit = useSettingValueAt<string>(SettingLevel.DEVICE, "use_system_theme", null, false, true);
+    const themeExplicit = useSettingValueAt<string>(SettingLevel.DEVICE, "theme", null, false, true);
+    const systemThemeActivated = useSettingValue<boolean>("use_system_theme");
+
+    // If the user has enabled system theme matching, use that.
+    if (systemThemeExplicit) {
+        return {
+            theme: themeChoice,
+            systemThemeActivated: true,
+        };
+    }
+
+    // If the user has set a theme explicitly, use that (no system theme matching)
+    if (themeExplicit) {
+        return {
+            theme: themeChoice,
+            systemThemeActivated: false,
+        };
+    }
+
+    // Otherwise assume the defaults for the settings
+    return {
+        theme: themeChoice,
+        systemThemeActivated,
+    };
+}

src/i18n/strings/en_EN.json

@@ -2420,21 +2420,21 @@
             "custom_font_description": "Set the name of a font installed on your system & %(brand)s will attempt to use it.",
             "custom_font_name": "System font name",
             "custom_font_size": "Use custom size",
-            "custom_theme_add_button": "Add theme",
-            "custom_theme_error_downloading": "Error downloading theme information.",
+            "custom_theme_add": "Add custom theme",
+            "custom_theme_downloading": "Downloading custom theme…",
+            "custom_theme_error_downloading": "Error downloading theme",
+            "custom_theme_help": "Enter the URL of a custom theme you want to apply.",
             "custom_theme_invalid": "Invalid theme schema.",
-            "custom_theme_success": "Theme added!",
-            "custom_theme_url": "Custom theme URL",
             "dialog_title": "<strong>Settings:</strong> Appearance",
             "font_size": "Font size",
             "font_size_default": "%(fontSize)s (default)",
+            "high_contrast": "High contrast",
             "image_size_default": "Default",
             "image_size_large": "Large",
             "layout_bubbles": "Message bubbles",
             "layout_irc": "IRC (Experimental)",
             "match_system_theme": "Match system theme",
-            "timeline_image_size": "Image size in the timeline",
-            "use_high_contrast": "Use high contrast"
+            "timeline_image_size": "Image size in the timeline"
         },
         "automatic_language_detection_syntax_highlight": "Enable automatic language detection for syntax highlighting",
         "autoplay_gifs": "Autoplay GIFs",

src/settings/SettingsStore.ts

@@ -355,7 +355,7 @@ export default class SettingsStore {
         const setting = SETTINGS[settingName];
         const levelOrder = getLevelOrder(setting);
 
-        return SettingsStore.getValueAt(levelOrder[0], settingName, roomId, false, excludeDefault);
+        return SettingsStore.getValueAt<T>(levelOrder[0], settingName, roomId, false, excludeDefault);
     }
 
     /**
@@ -369,13 +369,13 @@ export default class SettingsStore {
      * @param {boolean} excludeDefault True to disable using the default value.
      * @return {*} The value, or null if not found.
      */
-    public static getValueAt(
+    public static getValueAt<T = any>(
         level: SettingLevel,
         settingName: string,
         roomId: string | null = null,
         explicit = false,
         excludeDefault = false,
-    ): any {
+    ): T {
         // Verify that the setting is actually a setting
         const setting = SETTINGS[settingName];
         if (!setting) {

src/theme.ts

@@ -103,7 +103,7 @@ export function enumerateThemes(): { [key: string]: string } {
     return Object.assign({}, customThemeNames, BUILTIN_THEMES);
 }
 
-interface ITheme {
+export interface ITheme {
     id: string;
     name: string;
 }

test/components/views/settings/ThemeChoicePanel-test.tsx

@@ -15,15 +15,177 @@ limitations under the License.
 */
 
 import React from "react";
-import { render } from "@testing-library/react";
+import { act, render, screen, waitFor } from "@testing-library/react";
+import { mocked, MockedObject } from "jest-mock";
+import userEvent from "@testing-library/user-event";
+import fetchMock from "fetch-mock-jest";
 
-import * as TestUtils from "../../../test-utils";
-import ThemeChoicePanel from "../../../../src/components/views/settings/ThemeChoicePanel";
+import { ThemeChoicePanel } from "../../../../src/components/views/settings/ThemeChoicePanel";
+import SettingsStore from "../../../../src/settings/SettingsStore";
+import ThemeWatcher from "../../../../src/settings/watchers/ThemeWatcher";
+import { SettingLevel } from "../../../../src/settings/SettingLevel";
+
+jest.mock("../../../../src/settings/watchers/ThemeWatcher");
+
+describe("<ThemeChoicePanel />", () => {
+    /**
+     * Enable or disable the system theme
+     * @param enable
+     */
+    async function enableSystemTheme(enable: boolean) {
+        await SettingsStore.setValue("use_system_theme", null, SettingLevel.DEVICE, enable);
+    }
+
+    /**
+     * Set the theme
+     * @param theme
+     */
+    async function setTheme(theme: string) {
+        await SettingsStore.setValue("theme", null, SettingLevel.DEVICE, theme);
+    }
+
+    beforeEach(async () => {
+        mocked(ThemeWatcher).mockImplementation(() => {
+            return {
+                isSystemThemeSupported: jest.fn().mockReturnValue(true),
+            } as unknown as MockedObject<ThemeWatcher>;
+        });
+
+        await enableSystemTheme(false);
+        await setTheme("light");
+    });
 
-describe("ThemeChoicePanel", () => {
     it("renders the theme choice UI", () => {
-        TestUtils.stubClient();
         const { asFragment } = render(<ThemeChoicePanel />);
         expect(asFragment()).toMatchSnapshot();
     });
+
+    describe("theme selection", () => {
+        describe("system theme", () => {
+            it("should disable Match system theme", async () => {
+                render(<ThemeChoicePanel />);
+                expect(screen.getByRole("checkbox", { name: "Match system theme" })).not.toBeChecked();
+            });
+
+            it("should enable Match system theme", async () => {
+                await enableSystemTheme(true);
+
+                render(<ThemeChoicePanel />);
+                expect(screen.getByRole("checkbox", { name: "Match system theme" })).toBeChecked();
+            });
+
+            it("should change the system theme when clicked", async () => {
+                jest.spyOn(SettingsStore, "setValue");
+
+                render(<ThemeChoicePanel />);
+                act(() => screen.getByRole("checkbox", { name: "Match system theme" }).click());
+
+                // The system theme should be enabled
+                expect(screen.getByRole("checkbox", { name: "Match system theme" })).toBeChecked();
+                expect(SettingsStore.setValue).toHaveBeenCalledWith("use_system_theme", null, "device", true);
+            });
+        });
+
+        describe("theme selection", () => {
+            it("should disable theme selection when system theme is enabled", async () => {
+                await enableSystemTheme(true);
+                render(<ThemeChoicePanel />);
+
+                // We expect all the themes to be disabled
+                const themes = screen.getAllByRole("radio");
+                themes.forEach((theme) => {
+                    expect(theme).toBeDisabled();
+                });
+            });
+
+            it("should enable theme selection when system theme is disabled", async () => {
+                render(<ThemeChoicePanel />);
+
+                // We expect all the themes to be disabled
+                const themes = screen.getAllByRole("radio");
+                themes.forEach((theme) => {
+                    expect(theme).not.toBeDisabled();
+                });
+            });
+
+            it("should have light theme selected", async () => {
+                render(<ThemeChoicePanel />);
+
+                // We expect the light theme to be selected
+                const lightTheme = screen.getByRole("radio", { name: "Light" });
+                expect(lightTheme).toBeChecked();
+
+                // And the dark theme shouldn't be selected
+                const darkTheme = screen.getByRole("radio", { name: "Dark" });
+                expect(darkTheme).not.toBeChecked();
+            });
+
+            it("should switch to dark theme", async () => {
+                jest.spyOn(SettingsStore, "setValue");
+
+                render(<ThemeChoicePanel />);
+
+                const darkTheme = screen.getByRole("radio", { name: "Dark" });
+                const lightTheme = screen.getByRole("radio", { name: "Light" });
+                expect(darkTheme).not.toBeChecked();
+
+                // Switch to the dark theme
+                act(() => darkTheme.click());
+                expect(SettingsStore.setValue).toHaveBeenCalledWith("theme", null, "device", "dark");
+
+                // Dark theme is now selected
+                await waitFor(() => expect(darkTheme).toBeChecked());
+                // Light theme is not selected anymore
+                expect(lightTheme).not.toBeChecked();
+                // The setting should be updated
+                expect(SettingsStore.setValue).toHaveBeenCalledWith("theme", null, "device", "dark");
+            });
+        });
+    });
+
+    describe("custom theme", () => {
+        const aliceTheme = { name: "Alice theme", is_dark: true, colors: {} };
+        const bobTheme = { name: "Bob theme", is_dark: false, colors: {} };
+
+        beforeEach(async () => {
+            await SettingsStore.setValue("feature_custom_themes", null, SettingLevel.DEVICE, true);
+            await SettingsStore.setValue("custom_themes", null, SettingLevel.DEVICE, [aliceTheme]);
+        });
+
+        it("should render the custom theme section", () => {
+            const { asFragment } = render(<ThemeChoicePanel />);
+            expect(asFragment()).toMatchSnapshot();
+        });
+
+        it("should add a custom theme", async () => {
+            jest.spyOn(SettingsStore, "setValue");
+            // Respond to the theme request
+            fetchMock.get("http://bob.theme", {
+                body: bobTheme,
+            });
+
+            render(<ThemeChoicePanel />);
+
+            // Add the new custom theme
+            const customThemeInput = screen.getByRole("textbox", { name: "Add custom theme" });
+            await userEvent.type(customThemeInput, "http://bob.theme");
+            screen.getByRole("button", { name: "Add custom theme" }).click();
+
+            // The new custom theme is added to the user's themes
+            await waitFor(() =>
+                expect(SettingsStore.setValue).toHaveBeenCalledWith("custom_themes", null, "account", [
+                    aliceTheme,
+                    bobTheme,
+                ]),
+            );
+        });
+
+        it("should display custom theme", () => {
+            const { asFragment } = render(<ThemeChoicePanel />);
+
+            expect(screen.getByRole("radio", { name: aliceTheme.name })).toBeInTheDocument();
+            expect(screen.getByRole("listitem", { name: aliceTheme.name })).toBeInTheDocument();
+            expect(asFragment()).toMatchSnapshot();
+        });
+    });
 });

test/components/views/settings/__snapshots__/ThemeChoicePanel-test.tsx.snap

@@ -1,73 +1,774 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`ThemeChoicePanel renders the theme choice UI 1`] = `
+exports[`<ThemeChoicePanel /> custom theme should display custom theme 1`] = `
 <DocumentFragment>
   <div
-    class="mx_SettingsSubsection"
-    data-testid="mx_ThemeChoicePanel"
+    class="mx_SettingsSubsection mx_SettingsSubsection_newUi"
+    data-testid="themePanel"
   >
     <div
       class="mx_SettingsSubsectionHeading"
     >
       <h3
-        class="mx_Heading_h4 mx_SettingsSubsectionHeading_heading"
+        class="mx_Heading_h3 mx_SettingsSubsectionHeading_heading"
       >
         Theme
       </h3>
     </div>
     <div
-      class="mx_SettingsSubsection_content"
+      class="mx_SettingsSubsection_content mx_SettingsSubsection_content_newUi"
     >
-      <div
-        class="mx_ThemeChoicePanel_themeSelectors"
-        data-testid="theme-choice-panel-selectors"
+      <form
+        class="_root_148br_24"
       >
-        <label
-          class="mx_StyledRadioButton mx_ThemeSelector_light mx_StyledRadioButton_disabled mx_StyledRadioButton_outlined"
+        <div
+          class="_inline-field_148br_40"
         >
-          <input
-            disabled=""
-            id="theme-light"
-            name="theme"
-            type="radio"
-            value="light"
-          />
-          <div>
-            <div />
-          </div>
           <div
-            class="mx_StyledRadioButton_content"
+            class="_inline-field-control_148br_52"
           >
-            Light
+            <div
+              class="_container_qnvru_18"
+            >
+              <input
+                class="_input_qnvru_32"
+                id="radix-42"
+                name="systemTheme"
+                title=""
+                type="checkbox"
+              />
+              <div
+                class="_ui_qnvru_42"
+              />
+            </div>
           </div>
           <div
-            class="mx_StyledRadioButton_spacer"
-          />
-        </label>
-        <label
-          class="mx_StyledRadioButton mx_ThemeSelector_dark mx_StyledRadioButton_disabled mx_StyledRadioButton_outlined"
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67"
+              for="radix-42"
+            >
+              Match system theme
+            </label>
+          </div>
+        </div>
+      </form>
+      <form
+        class="_root_148br_24 mx_ThemeChoicePanel_ThemeSelectors"
+      >
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_enabled cpd-theme-light"
         >
-          <input
-            disabled=""
-            id="theme-dark"
-            name="theme"
-            type="radio"
-            value="dark"
-          />
-          <div>
-            <div />
-          </div>
           <div
-            class="mx_StyledRadioButton_content"
+            class="_inline-field-control_148br_52"
           >
-            Dark
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                checked=""
+                class="_input_1vw5h_26"
+                id="radix-43"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
           </div>
           <div
-            class="mx_StyledRadioButton_spacer"
-          />
-        </label>
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-43"
+            >
+              Light
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-dark"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-44"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="dark"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-44"
+            >
+              Dark
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-light"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-45"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light-high-contrast"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-45"
+            >
+              High contrast
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-dark"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-46"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="custom-Alice theme"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-46"
+            >
+              Alice theme
+            </label>
+          </div>
+        </div>
+      </form>
+      <div
+        class="mx_ThemeChoicePanel_CustomTheme"
+      >
+        <form
+          class="_container_zfn7i_17 mx_ThemeChoicePanel_CustomTheme_EditInPlace"
+          id=":r7:"
+        >
+          <div
+            class="_label_zfn7i_21"
+            id=":r8:"
+          >
+            Add custom theme
+          </div>
+          <div
+            class="_controls_zfn7i_27"
+          >
+            <input
+              aria-invalid="false"
+              aria-labelledby=":r8:"
+              class="_control_9gon8_18 _control_zfn7i_27"
+              value=""
+            />
+            <div
+              class="_button-group_zfn7i_32"
+            >
+              <button
+                aria-controls=":r7:"
+                aria-label="Add custom theme"
+                class="_button_zfn7i_32 _primary-button_zfn7i_51"
+                type="submit"
+              >
+                <svg
+                  class="cpd-icon"
+                  fill="currentColor"
+                  height="1em"
+                  viewBox="0 0 24 24"
+                  width="1em"
+                  xmlns="http://www.w3.org/2000/svg"
+                >
+                  <path
+                    d="M9.55 17.575c-.133 0-.258-.02-.375-.063a.878.878 0 0 1-.325-.212L4.55 13c-.183-.183-.27-.42-.263-.713.009-.291.105-.529.288-.712a.948.948 0 0 1 .7-.275.95.95 0 0 1 .7.275L9.55 15.15l8.475-8.475c.183-.183.42-.275.712-.275s.53.092.713.275c.183.183.275.42.275.712s-.092.53-.275.713l-9.2 9.2c-.1.1-.208.17-.325.212a1.106 1.106 0 0 1-.375.063Z"
+                  />
+                </svg>
+              </button>
+              <button
+                aria-controls=":r7:"
+                class="_button_zfn7i_32"
+                role="button"
+                type="button"
+              >
+                <svg
+                  class="cpd-icon"
+                  fill="currentColor"
+                  height="1em"
+                  viewBox="0 0 24 24"
+                  width="1em"
+                  xmlns="http://www.w3.org/2000/svg"
+                >
+                  <path
+                    d="M6.293 6.293a1 1 0 0 1 1.414 0L12 10.586l4.293-4.293a1 1 0 1 1 1.414 1.414L13.414 12l4.293 4.293a1 1 0 0 1-1.414 1.414L12 13.414l-4.293 4.293a1 1 0 0 1-1.414-1.414L10.586 12 6.293 7.707a1 1 0 0 1 0-1.414Z"
+                  />
+                </svg>
+              </button>
+            </div>
+          </div>
+          <span
+            class="_caption-line_zfn7i_92 _caption-text_zfn7i_130 _caption-text-help_zfn7i_147"
+          >
+            Enter the URL of a custom theme you want to apply.
+          </span>
+        </form>
+        <ul
+          class="mx_ThemeChoicePanel_CustomThemeList"
+        >
+          <li
+            aria-label="Alice theme"
+            class="mx_ThemeChoicePanel_CustomThemeList_theme"
+          >
+            <span
+              class="mx_ThemeChoicePanel_CustomThemeList_name"
+            >
+              Alice theme
+            </span>
+            <button
+              aria-label="Delete"
+              class="_icon-button_rijzz_17 _destructive_rijzz_78"
+              role="button"
+              style="--cpd-icon-button-size: 32px;"
+              tabindex="0"
+            >
+              <div
+                class="_indicator-icon_133tf_26"
+                style="--cpd-icon-button-size: 100%;"
+              >
+                <div />
+              </div>
+            </button>
+          </li>
+        </ul>
       </div>
     </div>
+    <div
+      class="_separator_144s5_17"
+      data-kind="primary"
+      data-orientation="horizontal"
+      role="separator"
+    />
+  </div>
+</DocumentFragment>
+`;
+
+exports[`<ThemeChoicePanel /> custom theme should render the custom theme section 1`] = `
+<DocumentFragment>
+  <div
+    class="mx_SettingsSubsection mx_SettingsSubsection_newUi"
+    data-testid="themePanel"
+  >
+    <div
+      class="mx_SettingsSubsectionHeading"
+    >
+      <h3
+        class="mx_Heading_h3 mx_SettingsSubsectionHeading_heading"
+      >
+        Theme
+      </h3>
+    </div>
+    <div
+      class="mx_SettingsSubsection_content mx_SettingsSubsection_content_newUi"
+    >
+      <form
+        class="_root_148br_24"
+      >
+        <div
+          class="_inline-field_148br_40"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_qnvru_18"
+            >
+              <input
+                class="_input_qnvru_32"
+                id="radix-32"
+                name="systemTheme"
+                title=""
+                type="checkbox"
+              />
+              <div
+                class="_ui_qnvru_42"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67"
+              for="radix-32"
+            >
+              Match system theme
+            </label>
+          </div>
+        </div>
+      </form>
+      <form
+        class="_root_148br_24 mx_ThemeChoicePanel_ThemeSelectors"
+      >
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_enabled cpd-theme-light"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                checked=""
+                class="_input_1vw5h_26"
+                id="radix-33"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-33"
+            >
+              Light
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-dark"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-34"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="dark"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-34"
+            >
+              Dark
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-light"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-35"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light-high-contrast"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-35"
+            >
+              High contrast
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-dark"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-36"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="custom-Alice theme"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-36"
+            >
+              Alice theme
+            </label>
+          </div>
+        </div>
+      </form>
+      <div
+        class="mx_ThemeChoicePanel_CustomTheme"
+      >
+        <form
+          class="_container_zfn7i_17 mx_ThemeChoicePanel_CustomTheme_EditInPlace"
+          id=":r1:"
+        >
+          <div
+            class="_label_zfn7i_21"
+            id=":r2:"
+          >
+            Add custom theme
+          </div>
+          <div
+            class="_controls_zfn7i_27"
+          >
+            <input
+              aria-invalid="false"
+              aria-labelledby=":r2:"
+              class="_control_9gon8_18 _control_zfn7i_27"
+              value=""
+            />
+            <div
+              class="_button-group_zfn7i_32"
+            >
+              <button
+                aria-controls=":r1:"
+                aria-label="Add custom theme"
+                class="_button_zfn7i_32 _primary-button_zfn7i_51"
+                type="submit"
+              >
+                <svg
+                  class="cpd-icon"
+                  fill="currentColor"
+                  height="1em"
+                  viewBox="0 0 24 24"
+                  width="1em"
+                  xmlns="http://www.w3.org/2000/svg"
+                >
+                  <path
+                    d="M9.55 17.575c-.133 0-.258-.02-.375-.063a.878.878 0 0 1-.325-.212L4.55 13c-.183-.183-.27-.42-.263-.713.009-.291.105-.529.288-.712a.948.948 0 0 1 .7-.275.95.95 0 0 1 .7.275L9.55 15.15l8.475-8.475c.183-.183.42-.275.712-.275s.53.092.713.275c.183.183.275.42.275.712s-.092.53-.275.713l-9.2 9.2c-.1.1-.208.17-.325.212a1.106 1.106 0 0 1-.375.063Z"
+                  />
+                </svg>
+              </button>
+              <button
+                aria-controls=":r1:"
+                class="_button_zfn7i_32"
+                role="button"
+                type="button"
+              >
+                <svg
+                  class="cpd-icon"
+                  fill="currentColor"
+                  height="1em"
+                  viewBox="0 0 24 24"
+                  width="1em"
+                  xmlns="http://www.w3.org/2000/svg"
+                >
+                  <path
+                    d="M6.293 6.293a1 1 0 0 1 1.414 0L12 10.586l4.293-4.293a1 1 0 1 1 1.414 1.414L13.414 12l4.293 4.293a1 1 0 0 1-1.414 1.414L12 13.414l-4.293 4.293a1 1 0 0 1-1.414-1.414L10.586 12 6.293 7.707a1 1 0 0 1 0-1.414Z"
+                  />
+                </svg>
+              </button>
+            </div>
+          </div>
+          <span
+            class="_caption-line_zfn7i_92 _caption-text_zfn7i_130 _caption-text-help_zfn7i_147"
+          >
+            Enter the URL of a custom theme you want to apply.
+          </span>
+        </form>
+        <ul
+          class="mx_ThemeChoicePanel_CustomThemeList"
+        >
+          <li
+            aria-label="Alice theme"
+            class="mx_ThemeChoicePanel_CustomThemeList_theme"
+          >
+            <span
+              class="mx_ThemeChoicePanel_CustomThemeList_name"
+            >
+              Alice theme
+            </span>
+            <button
+              aria-label="Delete"
+              class="_icon-button_rijzz_17 _destructive_rijzz_78"
+              role="button"
+              style="--cpd-icon-button-size: 32px;"
+              tabindex="0"
+            >
+              <div
+                class="_indicator-icon_133tf_26"
+                style="--cpd-icon-button-size: 100%;"
+              >
+                <div />
+              </div>
+            </button>
+          </li>
+        </ul>
+      </div>
+    </div>
+    <div
+      class="_separator_144s5_17"
+      data-kind="primary"
+      data-orientation="horizontal"
+      role="separator"
+    />
+  </div>
+</DocumentFragment>
+`;
+
+exports[`<ThemeChoicePanel /> renders the theme choice UI 1`] = `
+<DocumentFragment>
+  <div
+    class="mx_SettingsSubsection mx_SettingsSubsection_newUi"
+    data-testid="themePanel"
+  >
+    <div
+      class="mx_SettingsSubsectionHeading"
+    >
+      <h3
+        class="mx_Heading_h3 mx_SettingsSubsectionHeading_heading"
+      >
+        Theme
+      </h3>
+    </div>
+    <div
+      class="mx_SettingsSubsection_content mx_SettingsSubsection_content_newUi"
+    >
+      <form
+        class="_root_148br_24"
+      >
+        <div
+          class="_inline-field_148br_40"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_qnvru_18"
+            >
+              <input
+                class="_input_qnvru_32"
+                id="radix-0"
+                name="systemTheme"
+                title=""
+                type="checkbox"
+              />
+              <div
+                class="_ui_qnvru_42"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67"
+              for="radix-0"
+            >
+              Match system theme
+            </label>
+          </div>
+        </div>
+      </form>
+      <form
+        class="_root_148br_24 mx_ThemeChoicePanel_ThemeSelectors"
+      >
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_enabled cpd-theme-light"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                checked=""
+                class="_input_1vw5h_26"
+                id="radix-1"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-1"
+            >
+              Light
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-dark"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-2"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="dark"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-2"
+            >
+              Dark
+            </label>
+          </div>
+        </div>
+        <div
+          class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector cpd-theme-light"
+        >
+          <div
+            class="_inline-field-control_148br_52"
+          >
+            <div
+              class="_container_1vw5h_18"
+            >
+              <input
+                class="_input_1vw5h_26"
+                id="radix-3"
+                name="themeSelector"
+                title=""
+                type="radio"
+                value="light-high-contrast"
+              />
+              <div
+                class="_ui_1vw5h_27"
+              />
+            </div>
+          </div>
+          <div
+            class="_inline-field-body_148br_46"
+          >
+            <label
+              class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+              for="radix-3"
+            >
+              High contrast
+            </label>
+          </div>
+        </div>
+      </form>
+    </div>
+    <div
+      class="_separator_144s5_17"
+      data-kind="primary"
+      data-orientation="horizontal"
+      role="separator"
+    />
   </div>
 </DocumentFragment>
 `;

test/components/views/settings/tabs/user/PreferencesUserSettingsTab-test.tsx

@@ -64,8 +64,13 @@ describe("PreferencesUserSettingsTab", () => {
         const mockGetValue = (val: boolean) => {
             const copyOfGetValueAt = SettingsStore.getValueAt;
 
-            SettingsStore.getValueAt = (level: SettingLevel, name: string, roomId?: string, isExplicit?: boolean) => {
-                if (name === "sendReadReceipts") return val;
+            SettingsStore.getValueAt = <T,>(
+                level: SettingLevel,
+                name: string,
+                roomId?: string,
+                isExplicit?: boolean,
+            ): T => {
+                if (name === "sendReadReceipts") return val as T;
                 return copyOfGetValueAt(level, name, roomId, isExplicit);
             };
         };

test/components/views/settings/tabs/user/__snapshots__/AppearanceUserSettingsTab-test.tsx.snap

@@ -16,71 +16,134 @@ exports[`AppearanceUserSettingsTab should render 1`] = `
           class="mx_SettingsSection_subSections"
         >
           <div
-            class="mx_SettingsSubsection"
-            data-testid="mx_ThemeChoicePanel"
+            class="mx_SettingsSubsection mx_SettingsSubsection_newUi"
+            data-testid="themePanel"
           >
             <div
               class="mx_SettingsSubsectionHeading"
             >
               <h3
-                class="mx_Heading_h4 mx_SettingsSubsectionHeading_heading"
+                class="mx_Heading_h3 mx_SettingsSubsectionHeading_heading"
               >
                 Theme
               </h3>
             </div>
             <div
-              class="mx_SettingsSubsection_content"
+              class="mx_SettingsSubsection_content mx_SettingsSubsection_content_newUi"
             >
-              <div
-                class="mx_ThemeChoicePanel_themeSelectors"
-                data-testid="theme-choice-panel-selectors"
+              <form
+                class="_root_148br_24 mx_ThemeChoicePanel_ThemeSelectors"
               >
-                <label
-                  class="mx_StyledRadioButton mx_ThemeSelector_light mx_StyledRadioButton_disabled mx_StyledRadioButton_outlined"
+                <div
+                  class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_disabled cpd-theme-light"
                 >
-                  <input
-                    disabled=""
-                    id="theme-light"
-                    name="theme"
-                    type="radio"
-                    value="light"
-                  />
-                  <div>
-                    <div />
-                  </div>
                   <div
-                    class="mx_StyledRadioButton_content"
+                    class="_inline-field-control_148br_52"
                   >
-                    Light
+                    <div
+                      class="_container_1vw5h_18"
+                    >
+                      <input
+                        class="_input_1vw5h_26"
+                        disabled=""
+                        id="radix-0"
+                        name="themeSelector"
+                        title=""
+                        type="radio"
+                        value="light"
+                      />
+                      <div
+                        class="_ui_1vw5h_27"
+                      />
+                    </div>
                   </div>
                   <div
-                    class="mx_StyledRadioButton_spacer"
-                  />
-                </label>
-                <label
-                  class="mx_StyledRadioButton mx_ThemeSelector_dark mx_StyledRadioButton_disabled mx_StyledRadioButton_outlined"
+                    class="_inline-field-body_148br_46"
+                  >
+                    <label
+                      class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+                      for="radix-0"
+                    >
+                      Light
+                    </label>
+                  </div>
+                </div>
+                <div
+                  class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_disabled cpd-theme-dark"
                 >
-                  <input
-                    disabled=""
-                    id="theme-dark"
-                    name="theme"
-                    type="radio"
-                    value="dark"
-                  />
-                  <div>
-                    <div />
-                  </div>
                   <div
-                    class="mx_StyledRadioButton_content"
+                    class="_inline-field-control_148br_52"
                   >
-                    Dark
+                    <div
+                      class="_container_1vw5h_18"
+                    >
+                      <input
+                        class="_input_1vw5h_26"
+                        disabled=""
+                        id="radix-1"
+                        name="themeSelector"
+                        title=""
+                        type="radio"
+                        value="dark"
+                      />
+                      <div
+                        class="_ui_1vw5h_27"
+                      />
+                    </div>
                   </div>
                   <div
-                    class="mx_StyledRadioButton_spacer"
-                  />
-                </label>
-              </div>
+                    class="_inline-field-body_148br_46"
+                  >
+                    <label
+                      class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+                      for="radix-1"
+                    >
+                      Dark
+                    </label>
+                  </div>
+                </div>
+                <div
+                  class="_inline-field_148br_40 mx_ThemeChoicePanel_themeSelector mx_ThemeChoicePanel_themeSelector_disabled cpd-theme-light"
+                >
+                  <div
+                    class="_inline-field-control_148br_52"
+                  >
+                    <div
+                      class="_container_1vw5h_18"
+                    >
+                      <input
+                        class="_input_1vw5h_26"
+                        disabled=""
+                        id="radix-2"
+                        name="themeSelector"
+                        title=""
+                        type="radio"
+                        value="light-high-contrast"
+                      />
+                      <div
+                        class="_ui_1vw5h_27"
+                      />
+                    </div>
+                  </div>
+                  <div
+                    class="_inline-field-body_148br_46"
+                  >
+                    <label
+                      class="_label_148br_67 mx_ThemeChoicePanel_themeSelector_Label"
+                      for="radix-2"
+                    >
+                      High contrast
+                    </label>
+                  </div>
+                </div>
+              </form>
             </div>
+            <div
+              class="_separator_144s5_17"
+              data-kind="primary"
+              data-orientation="horizontal"
+              role="separator"
+            />
           </div>
           <div
             class="mx_SettingsSubsection"

test/components/views/spaces/QuickThemeSwitcher-test.tsx

@@ -21,17 +21,17 @@ import { mocked } from "jest-mock";
 
 import QuickThemeSwitcher from "../../../../src/components/views/spaces/QuickThemeSwitcher";
 import { getOrderedThemes } from "../../../../src/theme";
-import ThemeChoicePanel from "../../../../src/components/views/settings/ThemeChoicePanel";
 import SettingsStore from "../../../../src/settings/SettingsStore";
 import { SettingLevel } from "../../../../src/settings/SettingLevel";
 import dis from "../../../../src/dispatcher/dispatcher";
 import { Action } from "../../../../src/dispatcher/actions";
 import { mockPlatformPeg } from "../../../test-utils/platform";
+import { useTheme } from "../../../../src/hooks/useTheme";
 
-jest.mock("../../../../src/theme");
-jest.mock("../../../../src/components/views/settings/ThemeChoicePanel", () => ({
-    calculateThemeState: jest.fn(),
+jest.mock("../../../../src/hooks/useTheme", () => ({
+    useTheme: jest.fn(),
 }));
+jest.mock("../../../../src/theme");
 jest.mock("../../../../src/settings/SettingsStore", () => ({
     setValue: jest.fn(),
     getValue: jest.fn(),
@@ -59,9 +59,10 @@ describe("<QuickThemeSwitcher />", () => {
                 { id: "light", name: "Light" },
                 { id: "dark", name: "Dark" },
             ]);
-        mocked(ThemeChoicePanel).calculateThemeState.mockClear().mockReturnValue({
+
+        mocked(useTheme).mockClear().mockReturnValue({
             theme: "light",
-            useSystemTheme: false,
+            systemThemeActivated: false,
         });
         mocked(SettingsStore).setValue.mockClear().mockResolvedValue();
         mocked(dis).dispatch.mockClear();
@@ -85,9 +86,9 @@ describe("<QuickThemeSwitcher />", () => {
     });
 
     it("renders dropdown correctly when use system theme is truthy", () => {
-        mocked(ThemeChoicePanel).calculateThemeState.mockClear().mockReturnValue({
+        mocked(useTheme).mockClear().mockReturnValue({
             theme: "light",
-            useSystemTheme: true,
+            systemThemeActivated: true,
         });
         renderComponent();
         expect(screen.getByText("Match system")).toBeInTheDocument();