1713624 - Focusing parent when two sibling subframes have been focused results in inconsistent focus state

Status: RESOLVED FIXED

(Core :: DOM: UI Events & Focus Handling, defect, P2)

Description

[Neil Deakin]

The test added by bug 1712900 uncovers a bug that occurs only in fission mode:

The frame structure is:
A1
-> B
-> A2

A and B are two processes. A2 is a sibling frame of B.

The frame A2 starts out focused.

When B is then focused, A1's focus is updated correctly, however if window.focus() is then called on A1, process A's focusedWindow is set to or remains at A2, yet its active focused element is the frame for B.

This causes the test to fail when enable-fission is used.

The best way to reproduce this bug is to apply the patch in bug 1712900 and run test test with --enable-fission.

Comment 1

[Henri Sivonen (:hsivonen)]

(In reply to Neil Deakin from comment #0)

The best way to reproduce this bug is to apply the patch in bug 1712900 and run test test with --enable-fission.

Do you happen to have a test that's scoped only to this bug?

I wrote https://hsivonen.fi/fission-sibling.html but the permission check on window.focus() means the call is ignored.

Comment 2

[Neil Deakin]

Attachment: browser_promisefocus.js

This is a version of the test that just shows the issue.

Comment 3

[Henri Sivonen (:hsivonen)]

Attachment: Bug 1713624 - Null out mFocusedWindow when receiving OOP focused BrowsingContext.

Comment 4

[Henri Sivonen (:hsivonen)]

(In reply to Neil Deakin from comment #2)

This is a version of the test that just shows the issue.

To be clear, this test isn't expected to pass but to err out with the focused window being null during the assertion in the Fission case, right?

https://treeherder.mozilla.org/#/jobs?repo=try&revision=93686970ed4c00d1cce1c5e51154a2e9aa4f7aec

Comment 5

[Henri Sivonen (:hsivonen)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=186e5e1247b3573ff69ae982b06ad78cc2ac8598

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4562a5404ff3
Null out mFocusedWindow when receiving OOP focused BrowsingContext. r=NeilDeakin

Comment 7

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/4562a5404ff3