The ActivityPub extension ForgeFed for federation between different servers is not finished yet. AFAIK Forgejo contributors work closely together with other ForgeFed devs to bring it forward.
Please not! I'm happy that any link is opened using firefox so I can have my extensions enabled (uBlock Origin, Dark Reader), but using android's “custom tab” feature which doesn't take you out of the app.
You can try to use the Flatpak version of Steam. It has some downsides like not creating .desktop files at the right location (by default), but it works on my machine.
The ActivityPub extension ForgeFed for federation between different servers is not finished yet. AFAIK Forgejo contributors work closely together with other ForgeFed devs to bring it forward.