1470346 - Gesture activation should activate entire doctree branch

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, enhancement)

Description

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

Sometimes when video is playing, a preroll ad plays, and in some cases that may be in a cross origin iframe. If we require gesture activation to play, then the user will have to click once for the cross origin ad, and then once the preroll ad finishes, the user will have to click again to activate playback of the same origin content video.

This is annoying. Also once we start prompting for permission to autoplay with a doorhanger, this will be doubly annoying.

So we should change our gesture activation strategy so that a gesture activation anywhere in the doc tree activates the entire doc tree.

Comment 1

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

Attachment: Bug 1470346 - Gesture activate all documents in tab, even across origins, upon user interaction.

Sometimes when video is playing, a preroll ad plays, and that may be in a cross
origin iframe. If autoplay media is disabled, we require a user gesture in a
document before playback in that document is permitted, and we require each
origin to be gesture activated separately. So in the cross origin preroll video
add case, then the user will have to click once to unblock playback for the
cross origin ad, and then once the preroll ad finishes, the user will have to
click again to activate playback of the same origin content video.

This is a bad user experience.

So we should instead make gesture activation propagate up the doc tree
irrespective of crossing origins.  This way, when the user clicks to activate,
all documents in that tab are also also effectively gesture activated, and so
can autoplay.

Review commit: https://reviewboard.mozilla.org/r/252242/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/252242/

Comment 2

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

Comment on attachment 8986982 [details]
Bug 1470346 - Gesture activate all documents in tab, even across origins, upon user interaction.

https://reviewboard.mozilla.org/r/252242/#review259200

Yeah, I guess this is fine. Users don't know about random origins in iframes. For them page is page, and it is the top level thing only.

::: dom/base/nsDocument.cpp:12525
(Diff revision 1)
> -  return mUserHasActivatedInteraction;
> +  // If any ancestor document is activated, so are we.
> +  nsIDocument* doc = GetSameTypeParentDocument();
> +  while (doc) {
> +    if (doc->mUserGestureActivated) {
> +      // An ancestor is also activated. Record activation on the unactivated
> +      // sub-brranch to speed up future queries.

brranch

Comment 3

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

Comment on attachment 8986982 [details]
Bug 1470346 - Gesture activate all documents in tab, even across origins, upon user interaction.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/252242/diff/1-2/

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4cee97f375da
Gesture activate all documents in tab, even across origins, upon user interaction. r=smaug

Comment 5

[Eliza Balazs [:ebalazs_]]

https://hg.mozilla.org/mozilla-central/rev/4cee97f375da