I have also posted this in the Claris Community “Report a Product Issue” site.
Operating system: Win 10 Pro, version 2004, Build 19041.746, 64 Bit, 64 GB Ram
File hosted on FMS19
Client: FMP 18.104.22.168
I have three hosted files. All three exhibit the same behavior. Popover buttons are non-responsive. I also tested a non-hosted file by adding a popover. This file exhibited the same behavior. Closing and reopening the files have no effect. I did not try rebooting Windows. This first occurred about two weeks ago and recurred today.
Update #1 - I opened one of the three hosted files using FMP 22.214.171.124 from a different desktop computer (Win 10 Home, version 2004, Build 19041.746, 64 Bit, 32 GB Ram). This time, the popover buttons worked fine.