1774410 - Netflix stopped playing videos in 103 (Error M7121-1331)

Status: RESOLVED INVALID

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

Description

[krzysztof.krason]

Attachment: Screenshot 2022-06-15 at 15-08-37 Netflix.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.63 Safari/537.36

Steps to reproduce:

Install new Firefox 103 (similar timeframe like in my other bug for 103 ~ June 9 or 10).
Go to netflix.com and try to play any movie.

Actual results:

I get Netflix error M7121-1331

Expected results:

I should be able to see the movie, just like I did before the update from June 9-10.

When I try netflix.com on Firefox Beta everything works normally. So it looks like 103 update from that date broke several things (at least for me): issue with DRM playback, issue with gigantic scaling that can't be disabled (https://bugzilla.mozilla.org/show_bug.cgi?id=1773823).

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

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.

Comment 2

[Karl Tomlinson (:karlt)]

Would you be able to use mozregression for us to find what change caused the change in behavior, please?

Comment 3

[krzysztof.krason]

Sorry, I found the root cause: I changed the User-Agent reported by Firefox and this resulted in Netflix throwing that error. When I get back to the default user agent everything works.

Comment 4

[Karl Tomlinson (:karlt)]

Thanks for reporting back.