Shapes AND Pathfinder issues

Thank you for the video, Laura.

Based on it, I'm sorry to tell you that I have no idea what's going wrong there.

Hopefully some other participants may know and cure the issue.

I am pretty amused that you mentioned a storm that may have changed the entire game.

Apart from that, can you perhaps share at least one sample Illustrator file including some instructions that may explain the issue?

Thank you for responding.

I have checked all my settings and nothing has changed. The file I have been working on has many, many layers so itried closing it and creating a new file. Same problem.

I am also experiencing another level of curiosity. If I click anywhere on the artboard with the selction tool, my entire canvas goes blank. The Navigator and layers still show that there is artwork but it is gone from the screen.  Clicking the meatball on several different layers, after a time, causes the artwork and artboard to reappear but as soon as I click again with the selection tool, it all disappears again.

It's worth noting that a few days ago we had a massive lighting storm and there was a strike right outside my window. Lights went off momentarily as did my computer. Things were fine for a few days, but now am having issues.

...and also the Appearance panel (with one of the shapes selected).

I am wondering if you have something going on at the layers level that is somehow causing this. Can you post an image of your layers panel with it expanded please.