Open Bug 1779884 Opened 3 years ago Updated 2 years ago

YouTube videos are not cached to disk when UA is set to Chromium

Categories

(Core :: Audio/Video: Playback, defect, P3)

Product:
Core
Component:
Audio/Video: Playback
Version:
Firefox 104
Type:
defect

Tracking

()

Status:
UNCONFIRMED

People

(Reporter: tgnff242, Unassigned)

Details

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:104.0) Gecko/20100101 Firefox/104.0

Steps to reproduce:

  1. Clear your cache.
  2. Watch a video on yt.
  3. Observe the cache size on your disk.
  4. Set general.useragent.override to Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36.
  5. Clear your cache.
  6. Watch the video again.
  7. Observe the cache size on your disk.

Actual results:

The watched video is not cached when the user agent string is set to match Chromium's.

If you switch the UA of Chromium to match Firefox's, it will cache the video, as well.

Expected results:

This isn't a browser bug, but not caching the video seems desirable, and it's the default behaviour they push to their browser.

The Bugbug bot thinks this bug should belong to the 'Core::Audio/Video: Playback' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Component: Untriaged → Audio/Video: Playback
Product: Firefox → Core

I can't reproduce this on my Windows 10. After modifying the UA, I can still see cache size increasing when I check Clear Data, which is under about:preferences. Where did you observe the cache size? Do you see any size increasing when you click Clear Data? Do you see cache size changing when watching videos on other sites?

Thank you.

Blocks: media-triage
Flags: needinfo?(tgnff242)

Watching this video at 1080p to the end, I get 143MiB in disk cache (per about:preferences) when the UA is set to Firefox, but only 9.7MiB when it's set to Chromium.

As for other sites, I tried watching archived (non-live) videos on twitch.tv and vlive.tv and it seems that the latter behaves like YT, ie. depends on UA, and the first always caches to disk regardless of UA/browser. It's possible the behaviour is different for live videos, but it was harder for me to control.

Also, see Bug 1752022.

Flags: needinfo?(tgnff242)
No longer blocks: media-triage
Severity: -- → S4
Priority: -- → P3
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