Apologies for the delayed reply. Thanks a lot for the thoughtful review — you highlighted a few UX gaps I hadn’t noticed.
In the updated version (1.0.9.5) I’ve added shortcuts for Apply and for Select-end-of-video. Used together with Start, the three in sequence give the quick replay you described: Start at time t → End-at-end → Apply. It’s not a single keystroke, but it keeps everything within the existing interval framework without adding parallel modes.
This should work in fullscreen as well. The other UI issues will take a bit longer, but your pointers are very helpful — thank you!