I use it to inspect video frames by frames, particularly being able to go back one frame. VLC doesn't support it, this thread about the feature is hilarious https://forum.videolan.org/viewtopic.php?t=120627
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What's lovely is that it is indeed possible, but not trivial, and you can see Remi is sort of baiting to catch smart talented programmers to the project.
You can see the patience and long term horizon needed to lead a volunteer open source project. Time to study VLC more.
Thanks!