Mine is Local Send which is a FOSS alternative similar to air drop that works across a variety of devices.
Are there any FOSS apps that can do this? MPV can move frame by frame but moving back is so unusably slow.
Depends on the machine and… maybe other things. I used to think that, too, but on my current machines I can step backwards just fine.
It’s probably a much more intensive operation requiring processing a lot of the file from before and throwing away current buffers or something.
OpenShot. But that’s a video editor and not a conventional video player per se.