This block contains unexpected or invalid content [Solved?]

Beaver Builder
1

I encountered this error message (“This block contains unexpected or invalid content”) using WP 5.4.1 and BB 2.3.2.5.

I made a video showing what I saw, and how I fixed it at: https://www.youtube.com/watch?v=kQTjKmkzFxE

I believe choosing “Attempt Block Recovery” from the little menu on the right (seven seconds into the video) is the fix.

I think Gutenburg was right to complain: I found a problem in the HTML block - there was a duplicate closing tag that may have been throwing things off.

I corrected the HTML, and the problem has not reappeared.