I've been watching Michael Ossmann's video guides on SDR on Great Scott Gadgets. In his videos, he hovers over the TTF sink which displays frequencies, power and TTF. If I do this on OS X, I don't get this yellow popup - besides the fact that my TTF sink looks differently.
Is this a setting in gnuradio, or might it be an OS X issue? I'm running gnuradio 3.7.9.1.
Screenshot from my application:
EDIT: It appears that installing pyopengl solves this, as WX is falling back to "something". Install it using pip install pyopengl and restart gnuradio.
I think WX fell back to the non-GL version. As Marcus said, this can have a lot of reasons. On OSX, I was, however, only missing python-opengl. Maybe that's also your problem.
I agree that we should switch to QT in the long run, but since there are still several WX projects around, it might be worth having a working installation.
(Couldn't comment since I don't have the required reputation.)