Writer Font size change causes program to crash - known bug or me screwing up?

Whenever I try to change the size of the font in a text box, the entire document crashes closed. It will also crash all other open LibreOffice windows too.
Any suggestions and/or hearing of potential similar experiences would also be appreciated.

Does it also happen if you have started LibreOffice in Safe Mode (Help -> Restart in Safe Mode...). If not, most probably your LibreOffice user profile is corrupt).

And please: Add your operating system and your LibreOffice version.