127981 - Temporary graphical glitches moving positioned iframe over another iframe

Status: NEW

(Core :: Web Painting, defect, P3)

Description

[Brian Rogers]

Mozilla trunk build 2002022503.

Since bug 91516 has been resolved, iframes now paint in the correct order,
however, it appears there is still some drawing code which assumes the old
behaviour still exists.

The given URL is something I came up with by modifying the sticky notes XBL demo
to contain iframes.  You can see that as you move the note, the existing screen
content is moved according to the clipping that would have been in effect before
bug 91516 was fixed.  As soon as there's a break in the moving them, they get
repainted, and everything looks correct again.

I would guess this is due to some hack or workaround that can be removed now. 
CCing Robert O'Callahan, who fixed bug 91516 and may be interested in accepting
this one.

Comment 1

[Boris Zbarsky [:bzbarsky]]

confirmed on linux current trunk.

Comment 2

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

Yes, you will see transient badness during scrolling and some updates. As far as
I know the only way to fix this is to get rid of the native widgets associated
with IFRAMEs (and hopefully almost everything else). The new improved view
architecture will help with this but it's still a fair bit of work, so I don't
think it can be targeted at 1.0.

Comment 3

[José Jeria]

The URL in this bug does not work anymore. :-(

Comment 4

[Brian Rogers]

The URL itself works.  Maybe the server was down at the time, or perhaps you
meant to say the testcase is broken.  I checked, and there were two issues with
it that have come up with the latest build.

1.  The second note was moving along with the first one.  I took a look with the
DOM Inspector and found that it was putting the second div inside the first.  I
realized that Mozilla has stopped handling <div /> as a closed, empty tag, like
it should.  As a workaround, I changed it to <div></div>.  (Anyone have a bug
number?)

2.  The iframes in the sticky notes weren't opening mozilla.org and
mozillazine.org in them like they used to.  I realized that the "inherits=" in
the XBL stopped working.  I worked around it by hardcoding the URL for the
iframes in notes to mozilla.org.  This appears to be because of a change in XBL:
bug 119317, although I couldn't get xbl:inherits to work either.  Perhaps more
has changed, but it's not important here.

Anyway, the important thing is that I now fixed the testcase so that it is again
a good testcase for *this* bug.

Comment 5

[pieter theron]

Attachment: flashing of iframe when changing background color of containing div

Comment 6

[Bernard Osmond]

dont know if this is the same type of behaviour, but at my site, i have noticed
that when the cursor goes over a link, the iFrame on the page flickers, and
seems to ve drawn in the wrong place, then moved down. Which looks quite ugly.

url : http://n30n.isa-geek.org/?p=irc

are these the same problem, or should i file another bug ?

Comment 7

[Christian Schmidt]

Re: comment 6
I have filed bug 239706 for the problem about the IFRAME appearing briefly in
the top of the page.

BTW, the testcase in attachment 95902 [details] worksforme using Mozilla/5.0 (Windows; U;
Windows NT 5.1; en-US; rv:1.7b) Gecko/20040404 Firefox/0.8.0+.