Did you try Firefox in Safe Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf

What security software are you running?

for some reason youtube videos just keep loading and not playing it works with other browsers but not frefox

Are you by chance using a KN or N edition of Windows 10 ? https://support.mozilla.org/en-US/kb/fix-video-audio-problems-firefox-windows

The second photo not a screenshot doesn't help since that isn't YouTube. And links would help as well.

The second does look like a Youtube video if you look at the controls.

I get this problem too, but in both Windows 10 and Ubuntu 20.04.4 LTS, but only with FireFox 103.0. The issue was not present before Firefox upgraded in Ubuntu (I hadn't booted Linux in a while). I am seeing the issue with this URL: https://www.youtube.com/watch?v=4tin5z99VTk I have also seen it with a select few other URLs, which I didn't happen to save. I'll update with more if I come across any.

Note, I did try that URL with Chrome in Windows and it plays with no problem.

I have the rare case of the YT video not playing with just spinning circle in centre though a reload of page usually then loads the youtube video fine.

On Linux make sure you have packages like FFmpeg installed to have codecs like libavcodec so you can fully support the HTML5 players used on Youtube, Twitch, news sites all around for video, audio,(and games) as the Flash Player Plugin is not longer used nor supported.

It is just some videos and it doesn't matter if I am in Windows or Linux, so I doubt it's a codec issue. Most YT videos and other streaming content has no problem. It is just a Firefox issue and seems to be dependent on version - the latest version is worse than previous ones. Is there a log I can view and/or post that could shed some light on this?

I just tried that URL again and it played with no delay. I haven't changed a thing on my PC, so I assume there was a change at the YT end, or some other issue, like a call to a 3rd party, probably ad-related, site that was slow. Just doesn't make sense.

Note that that video looks like a video posted quite recently. In such a case YouTube may not have yet transcoded the video to all codecs it normally supports and thus can cause issues. That would explain why you can now play the video without problems.

In such a case you can check the Web Console.

• https://developer.mozilla.org/en-US/docs/Tools/Web_Console

Thanks! I'll check that next time. I suppose that there may be different codecs needed for FireFox vs Chrome or Edge. Would that explain why it loaded normally in Chrome?

Does the problem start after you have used the time normally for some time? And then it works again if you quit out of Firefox and start it up again? Some users have experienced that kind of connection issue after a period of use on Google Search, Gmail, and YouTube that is linked to a new feature called "zero round trip resumption" which is intended to speed up website connections. You can disable this feature to test whether that helps:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(2) In the search box in the page, type or paste security.tls.enable_0rtt_data and pause while the list is filtered

(3) Double-click the preference to switch the value from true to false

After that, try YouTube again in a new tab. Any improvement?

The problematic URL didn't work after restarting Firefox and, in fact, after rebooting entirely and even after loading Linux instead of Windows, using Firefox. I haven't run into a similar issue since this one, but I'll check on that if I do. Currently, security.tls.enable_0rtt_data is set true. What does that do?

Currently, security.tls.enable_0rtt_data is set true. What does that do?

It reduces the back-and-forth involved in making a connection between a browser and a web server when you are actively using the site (resumed connections). Cloudflare has an explainer post here: https://blog.cloudflare.com/introducing-0-rtt/.

I caught another non-loading URL today. The 0rtt_data change didn't help, but I found this message in the console: Source map error: Error: request failed with status 404 Resource URL: https://www.youtube.com/watch?v=AmHehWLRl8E Source Map URL: global_styles_sass.css.map

The URL noted above does load in Chrome. I would think that source map would be commonly used, so I don't understand the problem. I'm not having a problem with half-dozen or so other YT videos I just clicked on. All are fairly new, by the way, since I'm moving through my new video notification list.

Thanks!

A "source map" is a developer feature that shouldn't affect Firefox's ability to load and display the page.

When a YouTube page doesn't load or the video doesn't start, does it work to reload the page (Ctrl+R)?

Sometimes a seeming stall could be due to an ad blocker interacting with the player. Ad blocking add-ons are frequently updated to fix bugs, so such issues come and go from time to time.

Reloading has never helped. I don't have any addons enabled at all and don't usually use an ad blocker.

I got the same issue with this URL just now: https://www.youtube.com/watch?v=4MKU5EY51Js

The console warnings come up as: Autoplay is only allowed when approved by the user, the site is activated by the user, or media is muted. base.js:8766:33 Some cookies are misusing the recommended “SameSite“ attribute 43 Autoplay is only allowed when approved by the user, the site is activated by the user, or media is muted. base.js:8766:33 MouseEvent.mozPressure is deprecated. Use PointerEvent.pressure instead. base.js:1923:347 The resource at “https://i.ytimg.com/generate_204” preloaded with link preload was not used within a few seconds. Make sure all attributes of the preload tag are set correctly. watch The resource at “https://r3---sn-fvf-quf6.googlevideo.com/generate_204” preloaded with link preload was not used within a few seconds. Make sure all attributes of the preload tag are set correctly. watch The resource at “https://r3---sn-fvf-quf6.googlevideo.com/generate_204?conn2” preloaded with link preload was not used within a few seconds. Make sure all attributes of the preload tag are set correctly. watch Source map error: Error: request failed with status 404 Resource URL: https://www.youtube.com/watch?v=4MKU5EY51Js Source Map URL: global_styles_sass.css.map

XHRPOSThttps://play.google.com/log?format=json&hasfast=true&authuser=0 [HTTP/3 401 Unauthorized 32ms]

Hi ofrihaddad,

It seems like you're hit by bug1782322. Right now, the team is still trying to narrow down the regression range for this issue. Hopefully, we'll be able to hear more update soon.

You can try to adjust the video quality (away from auto) or un-maximize and reload the window to force a re-render to see if that makes the video start.

I ran into 2 more URLs that did this today and I changed the quality from Auto 480p to HD. The video played immediately. This seems like a bug in Mozilla. I've seen the following behavior - it freezes when quality is defaulted to Auto. If I change the quality setting 1080, 720 or 480p, explicitly, then reload the tab, the video plays just fine. If I reset to auto and reload, it may freeze (not entirely consistent) at either 480p or 720p. The latest URL I've seen this behavior: https://www.youtube.com/watch?v=ht6cz9vOnLk