The app lets you toggle mute for audio streams with a home screen widget. Note on Android 9+ third-party apps can no longer mute alarms. It has an optional timer that will automatically un-mute later. You can customize how much to set the volume to when un-muting. The app has lots of customization.

Features
🔊 Home Screen Widget to Toggle Mute
🔊 Optional Timer to Automatically Un-mute
🔊 Option to Disable Vibrate when Muted
🔊 Customize How Much to Set the Volume to When Un-muted
🔊 5 App Theme Choices: Auto, Dark, Light, Black Out, and Light Amber
🔊 Widget Color Customization
🔊 Choose Which Audio Streams to Mute
🔊 Home Screen Widget to Mute Individual Streams

Try the Lite Version
https://play.google.com/store/apps/details?id=com.grantojanen.audiomutelite

More Details
Offline: Yes
Lightweight: Yes, < 1MB
Multi-Window Support: Yes
Descriptor: quick audio mute toggle

Permissions Used
🔊 App requires permission to disable/enable "Do Not Disturb" mode (Android 6+ only.)
🔊 Un-mute Timer feature requires permission to run in the background at any time (Android 6+ only.)
🔊 Un-mute Timer feature requires permission to run on start up (in case the device is restarted while timer is set.)