Perhaps this will help
https://github.com/bluez/bluez/issues/673#issuecomment-1849132576
Perhaps this will help
https://github.com/bluez/bluez/issues/673#issuecomment-1849132576
Are you using the flatpak version of Steam, and if so does it require a bit of permission-fiddling to see controllers?
It does, and it supports Linux and macOS too
Readest (https://readest.com/) can also use KOReader sync and works on iOS, Windows, and on the web.