Error message org.freedesktop.Platform 20.08

Updating packages on my Ubuntu based Pop OS operating system recently I got an error message about the end of life of org.freedesktop.Platform 20.08

Looking for updates…
Info: org.freedesktop.Platform.GL.default//20.08 is end-of-life, with reason:
   org.freedesktop.Platform 20.08 is no longer receiving fixes and security updates. Please update to a supported runtime version.

Solving this is pretty straightforward and can be done in three steps.

First, check your list of flatpak packages

 flatpak list --runtime

You should see multiple Freedesktop SDK applications with the Application ID org.freedesktop.Sdk. You can see the version numbers as well. In my case, there were 20.8, 21.08.17.1, and 22.08.5.

Using the follwing command we can remove the end of life version:

 flatpak remove org.freedesktop.Sdk

Running this will give you an option where you can select the version. You should pick 20.08 and afterwards confirm that you want to remove additional folders and files.

You are done with cleaning up. For good measure you can also remove unused packages:

 flatpak uninstall --unused