1930594 - Don't emit "domContentLoaded" and "load" events when creating new top-level browsing contexts (tabs) when "about:blank" is loaded and emit contextCreated event at the end

Status: RESOLVED FIXED

(Remote Protocol :: WebDriver BiDi, task, P2)

Description

[Alexandra Borovova [:Sasha]]

After reading the html spec on the topic of creating a top-level browsing context with about:blank, I've noticed that in the browsing context creation algorithm we’re supposed to create and load a document, but it looks like it skips all the post parsing steps, where we’re supposed to send browsingContext.domContentLoaded and browsingContext.load events, and just jumps to the end of it (to the step 11). So it looks like per spec we shouldn’t send the load events. At the same time, it seems like we should send the browsingContext.contextCreated event almost at the end (see step 12) before we return.
According to Alex, if we don't send load events but send the contextCreated event when a tab is fully loaded, that should be enough for Puppeteer. But at the moment of this bug creation, Chrome sends the load events for such case and send browsingContext.contextCreated events very early (before load events).

Comment 1

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Moving it already to M14 as discussed yesterday in the meeting.

Comment 2

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Test updates will be synced soon via bug 1932829.

Comment 3

[Alexandra Borovova [:Sasha]]

Looks like since I've created this bug, Chrome updated their implementation, and they do not emit load events for "about:blank" anymore. But since there are no really requests to fix it now, I think it still makes sense to wait for bug 543435 to land before working on this bug.

Comment 5

[Holger Benl [:hbenl]]

Note that we currently send the load events for browsing contexts created with browsingContext.create and window.open("about:blank") but not for those created with window.open().

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Holger, mind testing again now that the about:blank load is happening synchronously?

Comment 7

[Holger Benl [:hbenl]]

(In reply to Henrik Skupin [:whimboo][⌚️UTC+2] from comment #6)

Holger, mind testing again now that the about:blank load is happening synchronously?

Firefox now always sends the load events for new browsing contexts (including those opened with window.open() which didn't get load events previously).

Comment 8

[Alexandra Borovova [:Sasha]]

Attachment: Bug 1930594 - [webdriver-bidi] Don't emit "domContentLoaded" and "load" events when "about:blank" is loaded.

Comment 9

[Alexandra Borovova [:Sasha]]

Attachment: Bug 1930594 - [webdriver-bidi] Send "browsingContext.contextCreated" event when "currentWindowGlobal" is available.

Comment 10

[Alexandra Borovova [:Sasha]]

Attachment: Bug 1930594 - [wdspec] Add test to verify that a script can be executed when "browsingContext.contextCreated" event is received.

Comment 11

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/60022 for changes under testing/web-platform/tests

Comment 12

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/f39ac162a8ef
https://hg.mozilla.org/mozilla-central/rev/b3a1f845bd17
https://hg.mozilla.org/mozilla-central/rev/6ee81a422e32

Comment 13

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR merged by moz-wptsync-bot