[Solution] Incompatible ratbagd API version (required: 2, provided: 1) with Flatpak Piper

[staticssleever668]

This problem is caused by changes in our back-end API - libratbag (libratbag/libratbag#1388).
As such, there are two ways to go about solving this:

1. Update libratbag
   Refer to libratbag installing wiki page: https://github.com/libratbag/libratbag/wiki/Installation
   This would be easy if the latest version of libratbag is already packaged for your distro.
   However, plenty of distro's don't package feature releases of programs, including big distros like Ubuntu. In such case you would have to build from source, or:

2. Use an older Piper version
   You can either roll-back the Flatpak, or use Piper from your distro's repo.
   To roll-back Flatpak Piper you can do:
   Run flatpak update --commit=72e3fe60e8b4b404ae9a750882d57f0c29eecca131bd5b0b505c8f223f0e8796 org.freedesktop.Piper.
   Then flatpak mask org.freedesktop.Piper to disable updates.
   If you want to enable updates again, do flatpak mask --remove org.freedesktop.Piper.

If you didn't have Piper before or uninstalled it, you may have to install a newer version first and only then rollback.

(the commit hash above can be found with flatpak remote-info --log flathub org.freedesktop.Piper.)