I have tried to run geany directly on Wayland after a while (i.e. without setting `GDK_BACKEND=x11`) and noticed that the autocomplete popups already work as expected. So the last thing to make geany 100% wayland ready is to fix the context menus.
I have updated #3011 and rebased it on current master. I have also tested that the context menus work fine with those changes. Can somebody please look at it and let me know if it is possible to merge it?