OK, I can reproduce (2) now when opening bigger documents and tried to fix it in
https://github.com/geany/geany-plugins/pull/1139
If you are able to compile the code, would you give it a try? This is a regression introduced in 1.38 (in an attempt to fix other problem) so I assume you are using the 1.38 release.
I'll try (1) tomorrow when I have access to an external keyboard with numlock.