I spoke too soon. The event viewer worked only briefly. It soon reverted to the broken behavior of not showing the event when I moved the cursor line over the event. Sometimes when I click on a photo, it will appear in the event viewer but when I click on a different photo the one visible in the event viewer does not change, and other times the viewer goes black and clicking on a photo or video shows nothing, just solid black. There is no rime or reason to any of this.
I don’t know if this relevant, but when the viewer is black and I move the cursor line over the video in the browser, the visible part of the event changes in the browser, not in the viewer, as I move the cursor line back and forth. This is not a viable alternative to seeing the changes in the viewer because the videos are too small in the browser and it is essentially impossible to do any useful selection with such tiny displays.
Obviously, I can’t delete the FCPX preferences every 2-10 minutes.