@refi64 err, my usecase is for audio plugins, which need to be self-contained.
This means each individual binary will have to contain its own copy of the entire libdecor..? 🤦‍♂️

Also libdecor also incorrectly assumes the buttons to be always on the right side 😔

Anyhow since my target is audio plugin UIs and they are mostly going to be embed in a host view, a super minimal hack for standalone windows using gtk and subsurfaces is quite ok with me, and that one gets the buttons correct