Hello seems a web attack or an update problem ?
fonts menus problems since version 9.
Fortunately I remember some shortcuts.
How to solve it ? (remove corrupted file and replace it ?
Can you please report the issue using Help->Contact Support in DbVisualizer? It will help us understanding your setup and environment.
In that new support request do also tell what fonts are set in Tools->Tool Properties under the General / Appearance / Fonts category?