gst_bus_remove_watch() fails silently
Removing a watch from the bus of a playbin will occasionally fail silently.
This can be reproduced by creating a cycle of calls to remove_watch and add_watch on the bus. After several cycles (~10-15), remove watch will fail silently and add_watch will return an error, presumably because there is already an existing watch on the bus.
I haven't yet created an simple reproducible example, but I will do so if this isn't a known issue.