I think this question was answered some time ago, possibly in a different (debian) forum, but I can't find the answer and it's bugging me. Some messages give me alternate ways to see the message while others don't (e.g. some Base messages have a pulldown for a fuller message).
I'm using 5.1.3.2 on a Debian/Stretch AMD64 system. The text in a lot of the pop-up messages (e.g. error messages) is unreadable. It's like the font is too small for there to be enough pixels to render it properly or something.
Possibly its the font size needs adjusting or possibly the font itself is corrupt (although it only happens in LibreOffice so it's not a font the desktop uses).
Any ideas on how to track this down and fix it?