GtkIMContextSimple ignores XCompose include directives
The current implementation of .XCompose files in gtkcomposetable.c ignores include directives in the XCompose files:
https://gitlab.gnome.org/GNOME/gtk/blob/master/gtk/gtkcomposetable.c#L216
For me, the most noticeable problem that this causes is that my ç became a ć after I added a custom XCompose file to my home directory. My language is set to pt-BR but since I have a US keyboard, I am used to typing ç via <dead_acute> <c> . When there is no XCompose file present, GtkIMContextSimple correctly loads the compose sequences from pt_BR.UTF-8/Compose that redefine <dead_acute> <c> to mean ç. However, if there is a .XCompose file in my home directory then the input method ignores pt_BR.UTF-8/Compose, even if I add a include "%L"
directive to the XCompose file. My current workaround is to copy paste the ç rules directly to my XCompose file.
I believe this bug is a specific subset of bug #645 (closed).
I don't know if the include directives have not been implemented due to lack of time, or due to some other reason. If it is the former, I would be interested in trying to help fix this. If it is the latter, then perhaps we can attempt a simpler fix? For example, supporting only include "%L"
would already help a lot.