Sorry, which extension is this? The only one I was able to find named "Open With" is pretty clearly not what you were referring to.

I prefer this one as it is potentially more secure than some of the other ones

https://github.com/grmat/play-with

This is the one I currently use: https://github.com/darktrojan/openwith Perhaps play-with is a better choice.

MPV is a player. https://mpv.io/

Oh, I know all about MPV. Invoking it cleanly from within Firefox is the part I was asking about (and which has been answered :)

That's what I do as well, and it's fantastic. Bonus functionality: Get MPV to always open on the second screen fullscreen (if you have one) and have it be always-on-top, small and on the bottom right corner when non-fullscreen, so you can just press Esc on the full-screen mpv window and get a PiP-like window.

samesame

also;

* rank up the cache settings in mpv to prebuffer the whole vid

* see the ytdl-format setting in mpv.conf to select a codec that your machine can decode in hardware for enhanced power efficiancy (lower fanspeed)

if you like vim like keybindings courtesy of tridactyl

bind V hint -W ! mpv to show a letter or letters adjacent to all links and open the one chosen in mpv. Normally most pages have few enough links visible that hints are either 1 or 2 characters. This means instead of picking up the mouse you can hit 3 keys.

You can get most pages down to 1 character if you craft your own custom selector, e.g. https://github.com/tridactyl/tridactyl/blob/dc8919e7e65d5dfa...

For the record we don't recommend piping straight to `!` as a malicious (and fairly Tridactyl specific) site could use it to execute whatever it wanted. We have a default bind for open in mpv that sanitises things - https://github.com/tridactyl/tridactyl/blob/dc8919e7e65d5dfa... using https://github.com/tridactyl/tridactyl/blob/dc8919e7e65d5dfa...

Thanks. A question occurs to me shouldn't such sanitation be its own step in order to be generalized to anything that the user wants to run?