Has anyone had a freeze from TWO sidebar icons blue at same time?

FCPX becomes unusable for me when this happens: The icon at the left is normally Blue for Libraries. When I click the icon for Titles and Generators it then properly then turns blue to show that I have selected it, but the other icon (Libraries) remains selected and blue, too! This puts FCPX in a state where no Titles or Generators will appear, and everything is stuck. Has anyone else seen this? It's happened a few times this year and again right now.
My info: Latest vers of FCPX. Latest OSX version. Mac Pro 2019 rediculously loaded in every way. Intel.
What I've tried: Deleting FCPX prefs both manually and Opt-Command at FCPX app start. I've uninstalled and reinstalled FCPX.

I've never once seen this happen even on my Intel units. My response is not at all helpful, so apologies for that.

The Mac Pro you have is probably a system that not a lot of people own, due to its absolutely bonkers price. So I'm wondering if it's something where the machine is at fault and not enough users out there to notice. Have you reported it to Apple using their feedback system?

Jim, other than trying to narrow down the conditions under which this occurs, I'd suggest possibly removing any third-party plugins or custom templates you may have installed to see if that helps. You could start with any customized or third-party generators, titles, or templates.

I have a modestly configured 2019 Mac Pro (and a 2012 Mac Pro) that I use with FCP and have never seen this behavior.

Dave, I have to think that must be the reason. I will try that and report back. Thank you.

Jim, a bit less likely cause might be due to any other software that is running while FCP is, such as CommandPost, Keyboard Maestro, input/mouse drivers, or other "automation utilities" (i.e., anything that could be triggered by UI "events")...

I'm OP with a possible solution. As DaveM mentioned it is probably caused by third party installs. In my case, plugin packages. I got a small utility from PFS that seems to have fixed what was jamming up fcpx. It's a little utility called FxRun that quote, "It's a script that relaunches the plugins used to run our products". I ran it as a regular application, I saw a lot of PFS dialogues flash by me, and now that it's done I no longer have the problem.

I have way too many plugin packages that I just don't need and will pare them way back. I hope this really is the solution, and that my post will help others. The link they gave me to FxRun is: pixelfxplugs.s3.us-west-1.amazonaws.com/PFS+FxRun.zip