gst-transcoder was ancient and required py3.6 for python-any-r1 and it didn't actually work with current gstreamer (well, 1.16 anyways, but probably various issues with 1.14 too, if not also completely broken), rendering pitivi mostly useless due to import issues. Additionally pitivi itself was only 3.6 supporting. So lets fast-stabilize this set to hopefully get back to a more working pitivi (pitivi is the only in-tree gst-transcoder consumer, though gst-transcoder can be used standalone via utility too), while fixing python3.7 migration issues too.
*** Bug 722250 has been marked as a duplicate of this bug. ***
amd64 stable
x86 stable. Closing.