1225554 - Clicking play button after pausing Youtube html5 video button does not resume video

Status: RESOLVED FIXED

(Firefox for Android Graveyard :: Audio/Video, defect)

Description

[Mike Taylor [:miketaylr]]

STR, In Fennec 42 (stable) and up:

1) Open youtube.com and select any video to play
2) tap the video to bring up controls and press the pause button
3) press play button

Expected:
Video plays

Actual:
Controls are hidden. Clicking the video after that causes the video to play.

It's not clear to me if this is our bug, or something that Youtube is doing. So let's find out.

Comment 1

[Mike Taylor [:miketaylr]]

I think the main issue that causes this is the difference between dispatching events from native video controls (we do and Chrome doesn't).

Here's a test page: https://miketaylr.com/bzla/controls.html. When you click play or pause, those events are dispatched to the <video> element in Fennec (and Firefox desktop), while they are not in Chrome Mobile (and desktop). 

Click + touch events dispatched on Video | No events dispatched on Video
-----------------------------------------|------------------------------
Firefox Desktop                          | Chrome Desktop
Firefox for Android                      | Chrome Mobile
Safari Desktop                           | 
Presto Opera                             | Opera Mobile
                                         | Edge Desktop

And then there's a few browsers that do special things:
Safari Mobile and FxiOS fire touchstart and touchend on the <video> wen you click play, but then the video is passed off to the system player. Clicking "Done" or pause don't send any events.

IE Mobile (Win Phone 8.2) dispatches touchstart and touchend (but not click) on the video.

Now I need to find out where in the Youtube JS to see if my theory is correct, and to help us decide if this is something that Youtube can easily work around or if we should investigate moving towards Chrome/Opera/Edge behavior.

Comment 2

[Mike Taylor [:miketaylr]]

Actually, this might be the wrong theory -- Firefox OS doesn't have the bug and also dispatches touchstart/touchend/click on the video. Time to dig back into Youtube...

Comment 3

[Mike Taylor [:miketaylr]]

On a hunch, I re-tested w/ the patch from 1217055 applied and the play button is back to working. 

Francisco, can you verify this is the behavior we want? To test without having to wait for that path to land, set the following to false in about:config, and refresh the page:

general.useragent.updates.enabled

The one difference between us and Chrome is that the only way to get a video playing again is via the controls. Chrome will let you click anywhere on the video -- but that's an implementation detail of their native controls. They stick a (fancy shadow-dom) play button on the video (the hit region happens to be the entire video), in addition to their controls below the video. See https://cloudup.com/cYCEnjIfNEF.

Comment 4

[[e-mail]]

Yep, that's that.. Thanks and have a great weekend!

Comment 5

[Mike Taylor [:miketaylr]]

This is fixed in Nightly, and I've requested uplift for Aurora and Beta over in https://bugzilla.mozilla.org/show_bug.cgi?id=1217055#c11. 

Can you verify (and close if working) in Nightly Francisco?

Comment 6

[[e-mail]]

It works. Hopefully it will hit Production in 43...

Comment 7

[Mike Taylor [:miketaylr]]

The patch was uplifted to beta and aurora, so assuming they stick it should land in 43.

Comment 8

[Kevin Brosnan [Ex-Mozilla]]

Let the bug with the patches track this.