In Android 11 when I had an active call and switched to another app I was used to have a circle with a letter and an animated earpiece somewhere on the screen, giving 4 options- hang up, speaker, mute, back to call.
Now I have almost nothing:
Got a small earpiece on the left and animated earpiece on the right and a small green dot for the active mic.
I disabled bubbles in settings | notifications | conversation since ‘Some conversations will appear as floating icos on top of other apps’ isn’t something that sounds tempting to me…
(Requires a reboot to work)
Read that for some people it wasn’t enough to delete app- cache and app- data, but they had to uninstall and reinstall the Google telephone app.
For the current version of the Google phone app (100.0.512999549) the ‘phone circle’ disappears after one call again and reappears after deleting app-data. The app cannot be completely uninstalled, but one can uninstall all updates, giving version 88.1.xxx. which seems to work reliably. So I disabled updates for the app.