Text widgets show plain text in edit/setup mode
Often when editing the contents of a text widget the widget displays in 'plain text' mode – it the font looks like Times New Roman, images/text don't go where they're told etc. It then reverts to normal formatting when going out of edit mode. This makes it very difficult to correctly format things without moving back and forth and using trial and error.
There doesn't seem to be any pattern to when this happens.