110160 - When several links are clicked sequentally, follow the last one.

Status: RESOLVED WORKSFORME

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

Description

[mozilla3eran]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:0.9.5) Gecko/20011011
BuildID:    2001101117

Netscape 4.x has the following convenient behavior. Say you click on some link
in the browser. For some time the old page remains visible while the new page
starts loading. During this time the old page remains responsive, and if you
click on a different link then then everything is reset and the second link is
followed. Mozilla does not reliably exhibit this behavior.

Reproducible: Sometimes
Steps to Reproduce:
1. Click on some link in the browser. 
2. Click on a different link quickly, but not too quickly (see below).

Actual Results:  Usually, the first link is followed anyway.

Expected Results:  Second link should be followed.

There's some timing issue involved. Apparently there are two stages following
the first click: 
I. Mozilla remains responsive and follows new clicks are desired. 
II. Mozilla still shows the old page, but is unresponsive and ignores clicks and
the ESC key.

Presumably stage I corresponds to the initiation of the new HTTP request, while
the second stage relates to layout of the new page.

The problem is very noticable because stage II takes a lot of time, and because
you're more likely to hit it (you waste the duration of stage I on noticing you
clicked the wrong link and moving the mouse).

Tested with Mozilla 0.9.5 on Win2K, Pentium 550MHz and 2001103121 on RedHat 7.2,
Celeron 660MHz.

Comment 1

[Jesse Houwing]

I can confirm current behaviour in 2001111203 in LINUX, Windows 2000, 98 and NT4

Comment 2

[Boris Zbarsky [:bzbarsky]]

ccing hyatt.  It sounds like stage II is paint suppression... (which is having
issues with timers, no?)

Comment 3

[John Levon]

Hi again Eran ;)

Looks like the right dupe to me, no ?

*** This bug has been marked as a duplicate of 78680 ***

Comment 4

[John Levon]

Gah, spoke too soon. Looking for mysterious event queue bug referenced

Comment 5

[Boris 'pi' Piwinger]

I can always get to the last clicked link. Is this still happening in a current
version?

pi

Comment 6

[John Levon]

It's certainly not, but it still should be duped to the right bug,
whatever it is.

Comment 7

[Boris Zbarsky [:bzbarsky]]

If this is no longer happening please just mark it worksforme and don't bother 
hunting for that one special bug.

Comment 8

[John Levon]

OK.

Comment 9

[mozilla3eran]

There is great improvement in recent builds -- the problematic time window
appears to have shrinked significantly. However, if you click a link just before
the new page is displayed then your click is still ignored. 
It's trickier to get the timing right now, but the problem is reproducible and
is bound to happen occasionally in real usage.

Comment 10

[John Levon]

Hehm, well I couldn't cause it to happen. Bz, did paint suppresion delay
get changed recently ? Is that all that changed ...

Do you know the root cause for this one.

Comment 11

[mozilla3eran]

I retract my comment #9. I think I do encounter the problem sporadically, but I
can't consistently reproduce it so maybe my perception is off by a few
milliseconds. WORKSFORME is fine with me.

By the way, if you get the timing of the second click right, you can now cause
the first link's target to be fully rendered and THEN replaced by the second
link's target, which may be confusing. Is it worth a bug?

Comment 12

[Boris 'pi' Piwinger]

Everybody seems to agree, that this is very special and you have to try hard to
make it happen. Not really a problem -> WFM.

pi