I have googled this issue a lot, and there is no definitive answer, although a lot of people do seem to be experiencing it. So I am posting my issue as a separate issue, even though it is quite similar to others.
A couple of days ago, pages I had previously been able to edit with the Visual Editor started acting strangely. The editor appeared differently - less functions, and text is white-on-white. I am able to select the text by dragging the cursor over it. I have images of this behaviour, but I am unsure how to share them with this forum.
Another symptom I have, and I believe it is related, is a warning message I am getting in the dashboard: Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 1966080 bytes)
Does anyone have any solutions to this issue please?
I have increased memory PHP can use (128M to 256M), I have increased memory WordPress can access from 32M to 128M (wp_config). I also tried adding adding a line into the .htaccess file, but this caused the site to crash.
Any thoughts and/or fixes would be much appreciated.