I think there is a bug in a specific way of building dashboard widgets on screen.
I could trace the bug but I don’t think this is the only way this happens.

First you need to have a dashboard with widgets like Display and Line, maybe more than one tab.
Then, the admin page must be opened in browser (Chrome v 95.0.4638.54 (Official Build) (x86_64)) many days - I never shutdown the notebook (MBP).
So, when I change to Edit mode, edit any widget and click Save or Back, the bug appears. Important: the left menu must be closed/collapsed.

So, if you just click on the menu icon to open/expand, all widgets back to work. You can try as many times as you want and it will behave like this. Otherwise, after editing a widget if you try to resize any (very small) widget, the bug affects permanently the size of all widgets. You will have to resize all widgets to original size and position (!!).

I didn’t understand why/when this happen for first time.
screen recording of this process: Dropbox - Screen Recording 2021-10-30 at 07.45.03.mov - Simplify your life