Final Cut Pro version 10.6 extremely slow!!!

I installed the 10.6 FCPX update on my 27" iMac (late 2015) and my editing has been extremely slow ever since. If I just add one transition between two clips, I have to wait a minute or two (with the rotating beachball) before I can do anything else.

I also tried it on my MacBook Pro (16" 2019) and it acts the same way. Very annoying and counter productive.

I also just updated both machines with the macOS Monterey version 12.0.1 iOS, however I was having the problems before I did that.

Is anyone else having this issue? Any suggestions?