Source on GitHub
Testing and Issues
You can test this app and submit issues during the testing period of the Android Contest 2021 contest.
Entries with serious issues will not be able to win the contest, but even minor issues might be important for overall results.
2. Fix: updated custom notification setting state after it changed. Commit https://github.com/rwqwr/Telegram/commit/ed16f5dfba71ad057fbee4e8913bc49dc9abcca7