On Reddit we had r/ImmaterialScience for these. Is there a community here too?

OBS is much crappier on linux than on windows, due to no AV1 encoding support.

OBS supports AV1 hardware encoding on linux with

• QSV (Intel) since 30.0
• VA-API (AMD/Intel) since 30.1
• NVENC (Nvidia) since 30.2

Software encoding has been supported for longer

Shelter uses the Work Profile. With android 15 you can enable Private Space, which is about the same, for a third instance of an app. Work profile requires an app that manages it like Shelter, private space just works.

There is a fork of Firefox Send

https://github.com/timvisee/send

If you already selfhost Bitwarden/Vaultwarden, you can use Bitwarden Send too.