Playground: Content disappears entirely from time to time

[Lotes]

Sometimes it can happen that the content disappears entirely. One source could be "fast typing" in the grammar editor.

But: the disappearing can also be an illusion in the regard of that the content editor is duplicated for some reason: The old content is moved down and the new content editor is empty.

Could this be a bug in the Monaco editor component? I think there was some issue, or? CC @kaisalmen