libav was the hostile fork, not FFmpeg. Someone removed write permissions from key contributors (or contributor. I forget) and just about everyone sided with th

libav was the hostile fork, not FFmpeg. Someone removed write permissions from key contributors (or contributor. I forget) and just about everyone sided with those contributors, thus the instigators were forced to rename their project. The development effort stayed on FFmpeg, even as the libav people tried porting back the changes. Eventually libav passed into irrelevance as it failed to acquire mindshare and distributions stopped including it.