Seems like I’ve found the culprit: https://github.com/Magisk-Modules-Alt-Repo/trichromelibrary-squoosh

When I deactivate this module and try again, the error message disappears and shows up again when enabled.

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Happy to hear that it changed for the better. I’m still on Android 10, where it sadly isn’t the default. But thanks for letting me know :)

I’d prefer that notifications are blocked by default (should be opt-in instead of opt-out). The only apps I NEED notifications for, are messaging apps, everything else is just annoying.