Visual aspect of advanced editor is invisible

The advanced layout editor is not showing the visual aspect, only the code. It did at first, but then it went away. Thanks to WordPress forums, I thought I found a way around the issue by clearing my browser’s cache whenever I ran into the problem. This made the text visible at least until I had to go ahead and create or work on another page, at which point I often needed to dump cookies again. It was a rather inconvenient solution, but it worked, that is, until it stopped working.