I was out walking today and wanted to control my VIRB 360 stuck on a monopod out of my backpack. The remote widget kept connecting and them almost immediately dropping into "Searching" on all options. I thought maybe the range or interference but then remembered that it was fine before when cycing. I selected a Walk activity (not started, just selected so it acquired sensors) and with that running the background the VIRB widget was 100% fine.
I repeated this test back at home multiple times. On it's own the VIRB widget drops the connection, activity with sensors acquired, widget is fine.
Tried a friend's Fenix 6S and the same camera in the same loccation and that worked 100% with just the widget and no activity selected.
Note: F/W 4.00 and a hard reset in the last 48 hours.