I found a solution for GTK2 (Geany 1.37). https://github.com/geany/geany/issues/1344#issuecomment-597588645 Now I have to figure out, how to apply it to GTK3... :)
P.S.: Thanks, **elextr**. You always try to help. -- You are receiving this because you are subscribed to this thread. Reply to this email directly or view it on GitHub: https://github.com/geany/geany/issues/2928#issuecomment-939720806