nextcloud-talk-android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  ~ Nextcloud Talk application
  ~
  ~ @author Mario Danic
  ~ Copyright (C) 2017-2019 Mario Danic <mario@lovelyhq.com>
  ~
  ~ This program is free software: you can redistribute it and/or modify
  ~ it under the terms of the GNU General Public License as published by
  ~ the Free Software Foundation, either version 3 of the License, or
  ~ at your option) any later version.
  ~
  ~ This program is distributed in the hope that it will be useful,
  ~ but WITHOUT ANY WARRANTY; without even the implied warranty of
  ~ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  ~ GNU General Public License for more details.
  ~
  ~ You should have received a copy of the GNU General Public License
  ~ along with this program.  If not, see <http://www.gnu.org/licenses/>.
  -->

<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
    <background android:drawable="@drawable/ic_launcher_background"/>
    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
</adaptive-icon>