I found an "emergency release" of 2.24.3 linked on the homepage to link against gstreamer:1.0 instead of 0.10, so I've just packaged that to get rid of vulnerable gstreamer usage. That "release" was uploaded to some Google Drive space instead of the usual, so I had to mirror it.
I also made latex stuff optional (it's used at runtime during quiz time if <latex> tag stuff is entered into a card, and if not found will just render that "latex render failed"). Also added a missing gnome-doc-utils build dep.
The only upstream change is linking against gstreamer-1.0 instead of 0.10, hence the immediately stable request to get it off security vulnerable version. There were actually no code changes, just what it links again, but it seems to work fine with new gstreamer with some flac file I tested - mainly because it's simple playback and during it's 0.10 times it never started to use playbin2 instead of playbin, so as gstreamer-1.0 renamed playbin2 to playbin, it just started to use the newer version, and successfully because it's a simple playback of file.
It should probably dep on gst-plugins-meta and such too, but didn't want to go too crazy on fixing up some maintainer-needed thing we might last rite soon for its libgnomeui and co usage...
ppc stable. Closing.