148075 - Portion of page repositions to different location after pressing "back" button

Status: VERIFIED DUPLICATE of bug 137982

(Core :: Layout, defect, P1)

Description

[fillup]

Reproducibility: most of the time under certain conditions

1. Go to www.salon.com .  Make sure the banner ad you're seeing is a flash
banner (the one I got that caused this is the "Try MSN" banner.  Refresh if
necessary.
2. Scroll down some in the page by moving the slider or the scroll wheel if
applicable.  Obscure the flash banner from view.
3.  Click on one of the "From the wires" news stories on the left.
4.  Make sure to scroll down an arbitrary amount on this page also.
5.  Hit Back button.
6.  Observe that Mozilla renders the page in the position you last viewed it,
meaning it's scrolled down some, but the flash content is layered over the top
in a position that appears to be what it WOULD be rendered at if the page were
being rendered from the top.

I will attach a pdf screenshot, as well as the HTML source.

Comment 1

[fillup]

Attachment: screenshot (pdf) of the bug in action

Comment 2

[fillup]

Attachment: the HTML source (detected "Netscape 5.0 on MacOS", actually running mozilla rc3)

Comment 3

[rubydoo123]

I do not see the misalignment on win98. Shrir: do you see this on Mac?

Comment 4

[shrirang khanzode]

i tried and I tried..but the msn ad banner is just not coming up. On other ads, 
this works fine, I tried a lot of times. I am not saying that this bug is 
invalid...but I can't reproduce it. Reporter, can u easliy repro this all the 
time with any other ad banner?Thx!

Comment 5

[fillup]

This is on mac os x.

Did you see the screenshot I attached?  It's definitely happening on my machine.

I'm sorry, I'm pretty new here, but I thought on the bugzilla form it said
"fields have been initialized from your user agent" but then again I don't find
them anywhere in this bugzilla record.

This is mac os x 10.1.4, running RC3 (the "regular" mozilla Carbon build for OS
X).  I can repro this every time now with this banner, am currently
investigating others.

Comment 6

[fillup]

It just happened again with another banner  -- this one was just a plain ol'
animated GIF so my "flash" diagnosis may be wrong -- on Salon.com, the same
site.  Their HTML looks fine (but I am no super-expert) so I can't figure this
out too easily.

Comment 7

[Peter Lubczynski]

um...how is this a plugin bug? I do not see any plugins in the testcase URL nor
in the attached HTML source.

Comment 8

[shrirang khanzode]

y'sir, I tried on the exact same OS , 10.1.4. No, u are doing great, but if u 
are seeing this sans the flash ad..i would say this might go to layout. Yes, I 
saw ur screenshot that's why I made my statement 'about not being invalid' since 
u provided proof :-)

Comment 9

[shrirang khanzode]

peter, once in a while, a flash ad pops up in the bkground.

Comment 10

[rubydoo123]

We always try to confirm what is stated, and that includes the OS, not all users
are able to test on different windows, mac and linux environments. Just because
it is reported on a particular platform is not an explicit indication of the
error only occuring on that platform.

Shrir: can you try this on Opera6 and IE to see what you get. Looking
through the HTML and I do not see anything unusual. Of course the last several
times that I refreshed the page I have not gotten the plug-in. However, the top
image, the one that was shown misaligned in the screenshot, is not a plug-in,
rather an animated gif.

As Peter stated, this looks more like a rendering issue.

Comment 11

[fillup]

Ok, thanks. I am trying to get into this mozilla bug-reporting thing by using it
every day, so forgive me if my bug reports make silly assumptions.  Thanks for
explaining.  Cheers!

Comment 12

[fillup]

Ok, I just accidentally reproduced this on another url by following the same
sequence:  load page with banner, scroll down, click link, scroll, hit "Back."

The url:
http://lasvegas.citysearch.com/profile/7022095/

The banner is an animated gif.  Will make an attm't of the HTML source.

Comment 13

[fillup]

Attachment: citysearch page that had the same problem

Comment 14

[Greg K.]

FWIW, a similar bug was also reported about a month back. I don't remember the #
offhand.

Comment 15

[Chris Petersen]

I saw a related problem on ebay's site when returning back to the main query.
Banner ad was repositioned over list of links returned from query. I was able to
break the test down to the simple form. Now, scrolling back to top of page
causes the banner content to not be displayed. Tested on OS X (2002-06-02-05 1.0.0).

Comment 16

[Chris Petersen]

Attachment: original page from ebay

Scroll to bottom of page and click on link. Go back to page. Notice top banner
ad is repositioned on page.

Comment 17

[Chris Petersen]

Attachment: Reduced test case

Resize window so that the horizontal scrollbar appears. Scroll down in page so
banner ad is no longer shown. Click on link. Go back to page. Scroll back up to
top of page. Banner is "grey" and is missing content.

Comment 18

[Chris Petersen]

I see this problem most of the time at ebay.com. I have attached a reduced test
case that reproduces what was described by the reporter. Appears to be a Mac
Only issue. Tested with the 2002-06-12-05 1.0.0 build.

Comment 19

[Chris Petersen]

*** Bug 150951 has been marked as a duplicate of this bug. ***

Comment 20

[Kevin McCluskey (gone)]

-> dcone. 

Comment 21

[fillup]

I have actually found another instance of this bug, or what __appears__ to be
another instance, rather.

It happened to me when reading articles on slashdot and macslash, using Moz 1.0
on OS X.  I found it because I was clicking those links in the discussion boards
that take you to another response, using #anchor urls.  So the process is:

1. Get deep into a slashdot story/message post.
2. click on the subject for a response (make sure you're being taken to a #
anchor url)
3. Notice the same error in drawing / laying out (again, seems to affect banner
ads, but maybe just coincidence?)

These pages change often, but here's where it happened:
http://www.macslash.org/articles/02/06/25/1629215.shtml  was the original page I
was on.

I clicked on the response to "Also a Networking Update" -- the response is
entitled "doh".  When I arrive on the page, and the shift-to-anchor operation
takes place, the amazon.com banner ad is laid over the actual comment.

Hasty conclusions drawn out of ignorance:
1. Maybe (maybe!!) this has something to do with whatever system in Moz / Gecko
that "shifts" pages down -- either for anchors or for back-button-derived shifting.
2. Maybe there's some way in which these banner ads are being coded at the HTML
level?  Because I haven't seen it in non-banner ad contexts.

I also saw a similar instance on the Business 2.0 website.  I don't know how to
describe it though, because I was browsing news.com and opening links in the
background.  When I got to that tab, the business 2.0 story had a bunch of the
notorious gray patches listed earlier in this bug.

Comment 22

[Waldemar Horwat]

This is the same as bug 157001.

Comment 23

[Kevin McCluskey (gone)]

*** Bug 157001 has been marked as a duplicate of this bug. ***

Comment 24

[Waldemar Horwat]

Copying attributes from bug 157001.

Note that this bug screws up the My Netscape web site.

Comment 25

[Robert O'Callahan (:roc) (email my personal email if necessary)]

It sounds like it might be to do with IFRAMEs. Can anyone find an example which
doesn't involve IFRAMEs?

Comment 26

[fillup]

Hello,

None of the pages I've seen this on involve IFRAMEs in anyway AFAIK.

cheers
fillup

Comment 27

[fillup]

Oh and it is happening to me on slashdot-powered sites a lot now, when I click
on individual comments to go to an anchor'ed link.

Comment 28

[Chris Petersen]

This problem with ebay (and other sites mentioned) can be reproduced in the
oldest OS X trunk (2002-05-10-03) and branch (2002-05-10-05) builds I could find.

Comment 29

[saari (gone)]

for some reason, Chimera does not reproduce this bug

Comment 30

[saari (gone)]

So who should own this? It is a pretty visible defect.

Comment 31

[Chris Petersen]

That is correct. I haven't been able to repro it in Chimera.

Comment 32

[saari (gone)]

and apparently it only happens on back, not forward. Salon seems to be the best
test case. Very odd.

Comment 33

[Christine Hoffman]

nominating for topembed

Comment 34

[fillup]

in response to the comment that this is a back-only bug, slashdot-powered sites
are the best test cases for the forward version of the bug (the anchor-url
cases).  Maybe others consider that a separate bug, but visually and
behaviorally (at least to this ignorant user!) it appears very similar.

Comment 35

[Greg K.]

Isn't this a duplicate of bug 137982?

Comment 36

[FZiegler]

*** Bug 144423 has been marked as a duplicate of this bug. ***

Comment 37

[FZiegler]

Attachment: Caught right on this page

This bug is now self-hosting: see what I got when I hit the reload button here,
after duping 144423. (Note also the ugly grey square in the lower left corner
-- I'm always getting this when there are 2 scrollbars, under Moz 1.1b for OS
X.)

Comment 38

[Chris Petersen]

Don,

Any new info on fixing this issue ? Do you think is the related to bug
http://bugzilla.mozilla.org/show_bug.cgi?id=137982 ? 

Comment 39

[Chris Petersen]

Occurs under OS X branch build (2002-07-31-05).

Comment 40

[Kevin McCluskey (gone)]

nsbeta1+

Comment 41

[FZiegler]

*** This bug has been marked as a duplicate of 137982 ***