Find the GTK3 pkg-config file and pick up a version using that.
- Do a clean rebuild
- Picks up the right GTK3 version and installs the right CSS file.
FTR, the reason this was not done at CMake time was to avoid depending on a development package (and associated dependencies like a compiler) to install something that's architecture-independent. My first. local patch I made at the time used pkg_config, but it was discarded for this reason.
Not that I have hard feelings about this, should this be changed, but I just wanted to outline the rationale for it at the time.
Understood, though I fear that hard coding the default leads to broken GTK themeing when the default gtk version in breeze gtk (3.18) is older than what a system might have ( for eg. 3.20 and above ).
This eliminates the ambiguity altogether.
I would argue that breeze-gtk should already have had this change in order to not break on systems where GTK is >= 3.20 and that introducing a new build-dep is the only way of fixing thee issue.