Cast it on any page with video or audio to take over whatever's playing: seek, change the speed, and loop between two points. The bar does it all with the mouse; the hotkeys do the same, and keep working with the bar hidden.
Good to know
Hotkeys stay quiet while you're typing in a text field.
Drag the bar aside by its handle, or hide it with ▾ — the hotkeys keep working either way.
It only reaches media the page hosts itself. The browser walls off a video embedded from somewhere else, though it works on the site the video came from.
The bar does all of this with the mouse. These hotkeys do the same without it — set as many as you like.
Jump the media forward or back by a set number of seconds.
Set an exact speed, or nudge the current one up and down. Pressing a speed key again returns to 1×.
Mark a start and an end and it plays that stretch on repeat until you clear it.