I just installed the latest Jitsi Meet from F-Droid. I am running Lineageos on microG on a Moto G7. When I start the app, I see the blue Jitsi screen, but then nothing further happens. This started when I upgraded to 20.5.0. Uninstalling and reinstalling did not fix it, but reverting to 20.4.2 is fine.
I do not know if this is just me or others are seeing this as well. It might be an issue caused by the way 20.5.0 works with microG. MicroG does not have Google Play Services, it has a mock for them. This is all explained here: https://microg.org/