So looking through the codebases for gtkglarea and gtkglext the contrast in approaches is pretty stark:
|separates platform specific code
|maintained for the moment
For my purposes, I think I’m best to port back to gtkglarea. It is maintained for now (not to slight the current maintainers, just we’ve been through this dance before).
I’ve done the port. Since kludge3d used gtkglarea in the past it wasn’t really that hard. So for now I’d say unless you need gtkglext’s extra features, use gtkglarea.