I am having the same issue on a 2019 MacBook Pro. Affects all browsers (Safari, Chrome and Firefox). I am running Avast for AV. Perhaps that is the issue?
For me since Catalina install iCloud tabs in Safari are un clickable 2 minutes after I open Safari. f I delete cache it will fix the problem if I restart Safari, but the problem will return after the next time I close and reopen Safari.
I'm beginning to be tired of Catalina Buggy software. I have bugs and glitches almost everywhere.