Ever wanted to open any app from the Notification shade? Now you can!
The button icon is generated as a monochrome version of the selected app icon - if the default threshold looks weird, adjust tap the icon and adjust the slider to your liking.
How to add / remove Quick Settings buttons: https://support.google.com/android/answer/9083864
Open Source:
https://github.com/bnutz/qs-app-launcheroo