As of three weeks ago, I can no longer edit Confluence pages with Chrome.
I currently use Version 90.0.4430.212 (Official Build) (64-bit).
When I click the Edit button, all that happens is I see the spinning wait icon, and I also often receive this banner (which, I might add, is not terribly helpful):

Firefox always works with no problem.
I have rebooted, cleared cache, logged out and back in to Confluence, uninstalled Chrome and re-installed, all these actions multiple times, and nothing works.
I use a server-based instance.