1803919 - Navigating back in history in Youtube may stay in the same page despite URL change. Tab title in history altered

Status: RESOLVED DUPLICATE of bug 1756970

(Core :: DOM: Navigation, defect)

Description

[Fanolian]

Attachment: YouTube go back 1 page new profile.mp4

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/109.0

Steps to reproduce:

1. In a new profile, go to https://www.youtube.com/ frontpage.
2. Left click any video to open it in the same tab.
3. Play the video. (skipping ads is optional. Reproducible even when an ad is playing)
4. Wait for a few seconds.
5. Go back; either by pressing the back button, laptop trackpad gesture, or the back function on a Logitech mouse.

Actual results:

Please refer to the attached video.
URL bar shows https://www.youtube.com/ but the video page remains. Video starts at the beginning again.
If I right click on the back/forward button, the title of https://www.youtube.com/ has been altered to the same as the video previously loaded. It shows the same in Library > History.

If the bug can't be reproduced, start a new YouTube tab and try again.

These are some profiles when the bug occurs:
Nightly preset: https://share.firefox.dev/3ulGZg1
Network preset: https://share.firefox.dev/3gX2GQC (I pressed back and forward a few times)

Expected results:

I should be able go back to Youtube frontpage.

I don't know if this is a Firefox regression or YouTube issue. I can't reproduce it in Chrome.
I can reproduce it in as early as 2022-02-25 build but I can't ensure a reasonable regression date as this occurs occasionally. pushlog for 02-25 build

There are other forum posts about this issue:
https://www.reddit.com/r/firefox/comments/yspxr1/go_back_one_page_bug_on_youtubecom/
https://www.reddit.com/r/firefox/comments/yzs3n7/go_back_one_page_bug_on_youtubecom/
https://www.reddit.com/r/firefox/comments/z7hogt/firefox_viewing_youtube_shorts/
https://www.reddit.com/r/firefox/comments/zb5qy3/frequent_glitch_when_watching_youtube_playlist/
https://support.mozilla.org/en-US/questions/1396987
https://support.mozilla.org/en-US/questions/1390748
https://support.mozilla.org/en-US/questions/1388535

Comment 1

[Frederik Braun [:freddy]]

I can reproduce the issue, but it's unclear to me if it's a Firefox or a YouTube bug. I'm hoping someone from the DOM Navigation team can dig deeper and maybe find the right kind of debug logging required for this.

Comment 2

[Frederik Braun [:freddy]]

OK, using DevTools I can intercept various load events, including 'popstate'. If I do that, I notice that the file desktop_polymer.js has a function handlePopstate, maybe that's doing something. I haven't looked much deeper.

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

See https://bugzilla.mozilla.org/show_bug.cgi?id=1756970#c34
and https://bugzilla.mozilla.org/show_bug.cgi?id=1803976