When I did not get a useful answer here, I went to explore the problem. More in depth than before. It turned out to be a mistake that stemmed from an upgrade / conversion from Laziest to Eaziest gallery.
The result was that I deleted the old gallery and reinstalled. The problem is now solved.
??? No one that can help ???? P L E A S EEEEEEE !!!
Same error. Waiting for a quick fix 😉
Same fault here.
I tried to switch to HTML mode and then back to VISUAL, then the text (content)appeared.
This solution has never faild in later use.