Manual for GIMP version 3 not available

After updating to version 3, the GIMP manual is not working anymore.

Running `flatpak uninstall --unused` after update, wants to uninstall `org.gimp.GIMP.Manual` (also gnome platform 46 and GMic plugin (which needs to be re-installed, selecting branch 3)).

Trying to re-install the manual, `org.gimp.GIMP.Manual` (branch 2.10, the only one available (same as the one that removed)) is installed (as "pinned" = won't get removed by `flatpak uninstall --unused` command anymore) and GIMP v3 won't use that.

Was this planned that the local manual is dropped completely and only online manual can be used with GIMP 3?

Review the org.gimp.GIMP.Manual Flatpak package and its available branches, starting with the reported 2.10 branch and GIMP version 3 behavior. Determine whether a version 3 manual package is expected and verify whether GIMP 3 can use it; document the supported outcome or identify the packaging change needed.

Written by the indexing model from the issue text.