diff --git a/src/components/views/dialogs/ModalWidgetDialog.tsx b/src/components/views/dialogs/ModalWidgetDialog.tsx
index 59eaab7b81..0c474b160c 100644
--- a/src/components/views/dialogs/ModalWidgetDialog.tsx
+++ b/src/components/views/dialogs/ModalWidgetDialog.tsx
@@ -1,5 +1,5 @@
 /*
-Copyright 2020 The Matrix.org Foundation C.I.C.
+Copyright 2020, 2021 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.
@@ -16,7 +16,7 @@ limitations under the License.
 
 import * as React from 'react';
 import BaseDialog from './BaseDialog';
-import { _t } from '../../../languageHandler';
+import { _t, getUserLanguage } from '../../../languageHandler';
 import AccessibleButton from "../elements/AccessibleButton";
 import {
     ClientWidgetApi,
@@ -39,6 +39,8 @@ import {OwnProfileStore} from "../../../stores/OwnProfileStore";
 import { arrayFastClone } from "../../../utils/arrays";
 import { ElementWidget } from "../../../stores/widgets/StopGapWidget";
 import {replaceableComponent} from "../../../utils/replaceableComponent";
+import {ELEMENT_CLIENT_ID} from "../../../identifiers";
+import SettingsStore from "../../../settings/SettingsStore";
 
 interface IProps {
     widgetDefinition: IModalWidgetOpenRequestData;
@@ -129,6 +131,9 @@ export default class ModalWidgetDialog extends React.PureComponent<IProps, IStat
             currentUserId: MatrixClientPeg.get().getUserId(),
             userDisplayName: OwnProfileStore.instance.displayName,
             userHttpAvatarUrl: OwnProfileStore.instance.getHttpAvatarUrl(),
+            clientId: ELEMENT_CLIENT_ID,
+            clientTheme: SettingsStore.getValue("theme"),
+            clientLanguage: getUserLanguage(),
         });
 
         const parsed = new URL(templated);
diff --git a/src/identifiers.ts b/src/identifiers.ts
new file mode 100644
index 0000000000..ebd8b87c99
--- /dev/null
+++ b/src/identifiers.ts
@@ -0,0 +1,17 @@
+/*
+ * Copyright 2021 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.
+ */
+
+export const ELEMENT_CLIENT_ID = "im.vector.web"; // root namespace for a lot of our settings
diff --git a/src/stores/widgets/StopGapWidget.ts b/src/stores/widgets/StopGapWidget.ts
index 17371d6d45..84cf35aeb4 100644
--- a/src/stores/widgets/StopGapWidget.ts
+++ b/src/stores/widgets/StopGapWidget.ts
@@ -1,5 +1,5 @@
 /*
- * Copyright 2020 The Matrix.org Foundation C.I.C.
+ * Copyright 2020, 2021 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.
@@ -52,6 +52,8 @@ import {getCustomTheme} from "../../theme";
 import CountlyAnalytics from "../../CountlyAnalytics";
 import { ElementWidgetCapabilities } from "./ElementWidgetCapabilities";
 import { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { ELEMENT_CLIENT_ID } from "../../identifiers";
+import { getUserLanguage } from "../../languageHandler";
 
 // TODO: Destroy all of this code
 
@@ -194,6 +196,9 @@ export class StopGapWidget extends EventEmitter {
             currentUserId: MatrixClientPeg.get().getUserId(),
             userDisplayName: OwnProfileStore.instance.displayName,
             userHttpAvatarUrl: OwnProfileStore.instance.getHttpAvatarUrl(),
+            clientId: ELEMENT_CLIENT_ID,
+            clientTheme: SettingsStore.getValue("theme"),
+            clientLanguage: getUserLanguage(),
         }, opts?.asPopout);
 
         const parsed = new URL(templated);