Instead of *.gpc, store the gproject settings in *.geany, removing the duplicates.
I would have to be able to add extra settings to .geany - not possible now.
Hi Jiri,
To do this catch the "project-open" and "project-save" signals from the Geany object, the user_data is a pointer to a GKeyFile of the current project.
So long as you use new key group names (preferably related to your plugin) there won't be any interference and you can also read all the other project settings.
Cheers lex