Makes the YouTube shortcuts work even if the player is not focused. Install Greasemonkey/Tampermonkey first, then click [Raw] to install.

youtube-global-shortcuts.user.js

// ==UserScript==
// @name         YouTube global shortcuts
// @namespace    https://gist.github.com/stefansundin/
// @homepage     https://gist.github.com/stefansundin/65e3d6db697636d8e7f1
// @downloadURL  https://gist.github.com/stefansundin/65e3d6db697636d8e7f1/raw/youtube-global-shortcuts.user.js
// @version      1.1
// @author       Stefan Sundin
// @description  Makes the YouTube shortcuts work even if the player is not focused.
// @icon         https://www.youtube.com/favicon.ico
// @match        https://www.youtube.com/*
// ==/UserScript==

// Space = Pause/play
// F = Toggle fullscreen
// M = Toggle mute
// P = Previous video (if in playlist)
// N = Next video (if in playlist)
// left and right keys focuses the button, but the first keydown won't trigger seeking unfortunately
// P and N already works without this userscript, but you must hold shift.
// Use Ctrl+Space to scroll down, Shift+Space to scroll up

window.addEventListener('keydown', function(e) {
  var button = document.getElementsByClassName('ytp-play-button')[0] || document.getElementById('movie_player');
  if (!button) return;
  console.log(e);

  // Skip if in comment reply form, or search field
  if (['TEXTAREA','INPUT'].indexOf(e.srcElement.tagName) !== -1 || ['yt-commentbox-text','yt-simplebox-text'].indexOf(e.srcElement.className) !== -1) return;

  var c = String.fromCharCode(e.keyCode).toLowerCase();
  if (c == ' ' || e.keyCode == 37 || e.keyCode == 39) { // 37 = left key, 39 = right key
    if (c == ' ' && (e.shiftKey || e.ctrlKey)) return;
    if (e.srcElement != button) {
      button.focus();
      if (c == ' ') button.click();
    }
  }
  else if (c == 'n') {
    document.getElementsByClassName('ytp-next-button')[0].click();
  }
  else if (c == 'p') {
    document.getElementsByClassName('ytp-prev-button')[0].click();
  }
});

Delicious! I use it in conjunction with Autohotkey to control the player without it having focus. and your script gives me access to everything. Speed control, play control, skipping, you name it - that was previously unattainable because the player always needed focus. You, SIr, are great!

Note: I am not currently using this script, so it might not work perfectly anymore.

But it looks like someone forked it and made some changes, so maybe this one works better if you have having issues: https://gist.github.com/yuryshulaev/b383dbb04256acea2f7a

I'm having trouble getting this to work. Can you please help me figure this out?

I downloaded Tampermonkey and installed it with the Raw button and tampermonkey says that the script is on when i visit a youtube page. But i dont see how i can program/use keyboard shortcuts. I tried the keyboard shortscuts listed in the script, but only the default keys are working when youtube is open. Is there somewhere that i can edit the different keyboard shortcuts? Is there somewhere in the script i need to edit? Or a setting in tampermonkey? I also use Keyboard Maestro, would that be helpful here?

Thanks, Dan

@DanKlim Sorry, I'm not using this anymore, and since they've redesigned YouTube several times, I don't think it works anymore.

I suggest that you check if the classes are the same, and try to use debug console.log statements to see what parts of the code runs. Hope you can get it working!

Can you make scripts that set a timer to automatically pause/stop on all Youtube embed videos? Like pause a video after X seconds!!?

For those who want a full keyboard navigation on YouTube check my Chrome extension: https://github.com/glaucocustodio/youcaptain

Man, you are a legend, thank you for making this. Can't believe Google is so bad at not implementing this.

Disclaimer: I have not used this for years and I doubt it still works. I think YouTube does have some global shortcuts these days, like the space key.

USE AT YOUR OWN RISK!

Yeah, thank you for the warning. What I wanted was a little simpler so I didn't use your code but learned from it. 🙏🙏