1378105 - Media is not blocked for previously unfocused closed tabs after restoring them from the History menu

Status: REOPENED

(Firefox :: Session Restore, defect, P3)

Description

[Emil Ghitta, QA [:emilghitta]]

Attachment: Restore Tabs From History.gif

[Affected versions]:
Firefox 56.0a1 (Build Id:20170703030203)

[Affected platforms]:
Windows 10 64bit
Mac 10.11.6
Ubuntu 16.04 64bit

[Steps to reproduce]:
1. Launch Firefox with a clean profile
2. Access the https://www.youtube.com/ webpage.
3. Open 2 random videos in new tabs without focusing them.
4. Close the previously 2 opened tabs without focusing them.
5. Restore the previously 2 closed tabs via History->Recently Closed tabs.

[Expected result]:
The first closed tab is focused and the media is played back. The second tab has the media blocked.

[Actual result]:
The second tab has the media unblocked as well.

[Regression range]:
I don't think that this is a regression but I will look into this if time permits.

[Additional Information]
Observe the attached video for more information regarding this issue.

Comment 1

[Emil Ghitta, QA [:emilghitta]]

Hi Alastor!

Can you please have look ? 

Thanks !

Comment 2

[Alastor Wu [:alwu]]

Will take a look later, thanks!

Comment 3

[Alastor Wu [:alwu]]

The page should be invisible after restore, but it seem the last tab would get the wrong visible status.

Media is resumed from [1], it should only be called when the tab goes to foreground. But we got this after restore, even the tab is on the background. Therefore, I think there might be something wrong during the session restore. 

[1] http://searchfox.org/mozilla-central/rev/e5b13e6224dbe3182050cf442608c4cb6a8c5c55/dom/base/nsDocument.cpp#12371

Comment 4

[Mike de Boer [:mikedeboer]]

Alastar, what you're saying in comment 3 means that this is something you'll own, right?

Comment 5

[Alastor Wu [:alwu]]

I could work on it, but I need some help from session restore team, because I have no idea why the visibility of second tab was wrong via "Recently Closed tabs".
Thanks!

Comment 6

[Mike de Boer [:mikedeboer]]

Alastor, I can help with this (the Sessionstore team is just me), but since time is quite limited on my end I can help mostly with issues/ explain how things work when you're stuck.
I hope you don't mind...

Comment 7

[Chris Pearce [:cpearce (Not reading bugmail)]]

This is fixed now. We're not playing media in background tabs that are restored.

Comment 8

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0
Build ID: 20180718220144

I can reproduce this issue on Windows 10 x64 on the latest Nightly 63.0a1(2018-07-18) using the STR from the description.
Chris, should we reopen this bug or log a new one?

Thanks

Comment 9

[Chris Pearce [:cpearce (Not reading bugmail)]]

Thanks, we should re-open. I don't think this needs to block shipping block-autoplay v2, but we should fix it.

Comment 10

[laszlo.bialis]

Reproduced on latest Nightly 68.0a1 (2019-03-31) (64-bit) on Ubuntu 16.04 x64

Comment 11

[Rares Doghi]

Hi, This issue no longer occurs since all media with sound is Blocked by Default, This issue can be reproduced only with Block Autoplay preference off.

When testing this issue make sure the media.autoplay.default = 0

Chris can you confirm this scenario ?

Thanks.

Comment 12

[Chris Pearce [:cpearce (Not reading bugmail)]]

What I see in Nightly is that every tab restored is foregrounded. Even with autoplay blocking disabled, we delay starting playback until the tab has been foregrounded. So if autoplay blocking is disabled, all restored YouTube tabs start playing immediately. So we can't avoid playback starting when restoring as long as we have the behaviour of restored tabs being foregrounded.

Basically, the issue as filed doesn't exist anymore, since I don't think it's possible to re-open tabs without foregrounding them.