i think you will find that gremlin is the problem. I did this years ago in a gtk3 branch.
Where can I find that gtk3-branch?
.
Maybe we can find a work arounf for gremlin
Hm, in my oppinion gremlin has no functional relevance.
So I'd like to get the rest working and than dedicate to problems around gremlin.
Grotius did promising steps in C++ - may be, that's a base for a new kind of gremlin?