Replaying a video on YouTube makes it buffer all over again instead of it playing instantly like Chrome does. Is there any fix for this?

KoolKai, 11 months ago

I just compared the behavior in both Chromium and Firefox on my machine, and as far as I can tell, they act the same.

Steps to reproduce:

1. Open a video: https://www.youtube.com/watch?v=erQ_9yEz0ls
2. Play the last 10 seconds
3. Click "replay" button in the YouTube player

What happens:

The buffer is cleared in both browsers.

What are you seeing that is different?

azureVM1, 11 months ago

You're supposed to let it play/buffer all the way till the end. Then press replay or when you're like 50-60% through the video, click on the timeline far enough back i.e < 1 min.

For example, when this video https://www.youtube.com/watch?v=2tdiKTSdE9Y finishes playing for me, and I press replay, YouTube starts rebuffering the video from scratch. In Chrome's case, the buffer is still there.

igorlogius, 11 months ago (edited 11 months ago)

not sure , but maybe it is media codec/encoding related?

You could maybe try addons.mozilla.org/en-US/…/enhanced-h264ify/ to check.

azureVM1, 11 months ago

It's not, because my CPU supports VP9 hardware decoding.

garam, 11 months ago

By anychance, do you have free ram? Sometimes this happen when the ram is not available… so yeah… You should check it first. Also check about:memory I guess

azureVM1, 11 months ago

Yes

garam, 11 months ago

Is the about:cache is full? Or it’s too small? I mean if it’s to small it could be the cause.

azureVM1, 11 months ago

I didn't know about that. It does seem small. It's just 32 MB. So I googled around and

http://kb.mozillazine.org/Browser.cache.memory.capacity

https://tweakguides.pcgamingwiki.com/Firefox_10.html

changed browser.cache.memory.capacity value from -1 to 1000000 and changed media.cache_readahead_limit / media.cache_resume_threshold to 999999 but I didn't notice any difference. Rebuffering still happens.

What I did notice was that after hitting the replay button, if I press right arrow quickly enough to skip forward (40% or more), the buffer reppears and my network activity reflects that.

So it seems to me is that Firefox caches about 60% of the video (latter half) and when you replay it, it starts rebuffering the lost 40% of the first half of the video. I reverted my settings back to default values (the 3 prefs I mentioned above) and it still behaves this way.

garam, 11 months ago

ugh, I’m out of idea tbh. Seems you need to ask others about it. Also are your video in 2k or probably 4k? or it’s normal 1080 or even only 720?

azureVM1, 11 months ago

Same. I even came across this comment after doing that. Did everything it said (browser.cache.offline.enable perf wasn't there for some reason, so I made one) and still no change. Changed the values of perfs mentioned in my post again as well, combined with that comment's proposed changes but still nothing.

And yeah, it's 1440p but I've tested this on 1080p videos as well. Length of 1440p video is 2-3 mins and the 1080p one is just over 11 mins.

Honestly, I give up at this point. Btw, thank you so much for trying to help.

BrianTheeBiscuiteer, 11 months ago

Wouldn’t surprise me if nothing could be done to fix this. It might help if the quality level was fixed instead of variable.

empireOfLove, 11 months ago

Nope. That’s one of the ways Google intentionally disadvantages browsers other than Chrome.

Install a user agent switcher and set it to the most recent Chrome agent string. You’ll probably see a long of jank go away…

azureVM1, 11 months ago

Yeah. And I actually tried changing user agent with this but still no luck. Tried incognito as well with chrome's UA. Re-buffers the same as always.