233164 - Mouse left click is lost when the viewport is panned

Status: RESOLVED FIXED

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

Description

[Isaac Hwak Han]

Regression between 040131 and 040205 (probably from fix of bug 20022).

Reproducing Steps:
1. Open the testcase
2. Click the link

Actual Result:
Left click is lost. No page transition.

This only happens when clicking a link pans the viewport to fit the focus
rectangle surrounding A element.

Middle and right click works fine.

Comment 1

[Isaac Hwak Han]

Attachment: testcase

Left click the link

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

It's worth noting that nsEventStateManager::CheckForAndDispatchClick isn't even
called.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

The pres shell isn't even getting the mouse up event.

Comment 4

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

... nor is the view manager, and the problem seems to be that a drag is being
initiated.

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I just relanded bug 20022 with this bug fixed.

Comment 6

[Jan Darmochwal]

Bug 288945 might have been caused by the fix for this bug (it was about the
time, when I first saw that bug). I have no idea what the fix for this bug is,
but David Baron refers to it in bug 50511 comment 64. There he mentions that the
right fix for this bug would be not to scroll when focusing due to a click.
Not scrolling when click-focusing would fix bug 105894 (Clicking a partially
off-screen link shouldn't scroll the page) and bug 288945 (clicking links in
client-side image maps scrolls the page).

Comment 7

[Jan Darmochwal]

Sorry for the spam. Just ignore my last comment, please. Bug 288945 might as
well have been caused by anything else, but not scrolling when click-focusing
sounds like a good idea.