Comment 142 for bug 1142213

> if we want to be extra sure, add a minimal requirement on the glib version in our (master) CMakefiles.
No, that's bad. This way you'll disable any older distros from being able to use latest oxygen-gtk release.

I'd suggest that we leave both variants - via popen() and g_spawn...() - and use popen() only for that glib version(s) which fails (and warn user in cmake output that current glib version is bad).