Bug 38427

Summary: Iframes in composited layers don’t repaint correctly (affects Yahoo! Mail with Flash Player 10.1)
Product: WebKit Reporter: Joe Strzemp <maccinema>
Component: New BugsAssignee: Nobody <webkit-unassigned>
Severity: Major CC: abarth, eric, mitz, simon.fraser, webkit.review.bot
Priority: P2 Keywords: InRadar, Regression
Version: 528+ (Nightly build)   
Hardware: Mac (Intel)   
OS: OS X 10.6   
URL: http://yahoo.com
Description Flags
Patch simon.fraser: review+

Description Joe Strzemp 2010-05-01 23:48:40 PDT
Scrolling in the content frame in yahoo mail (the "All-New Mail" version)
stopped working somewhere between build r56855 and r56912.

You have to select "Switch to All-New Mail" to see/use the separate
content window to reproduce its broken behavior.

Scrolling does work in Yahoo's mail content frame in Safari 4.0.5 and Firefox 3.6.3.

Problem still exists with r58638.

All testing done on OS X 10.6.3.
Comment 1 Mark Rowe (bdash) 2010-05-02 01:05:23 PDT
Comment 2 mitz 2010-05-03 15:30:39 PDT
I don’t seem to be able to reproduce with r58691, but maybe I don’t understand which frame is supposed to have issues. I can successfully scroll the preview pane below the message list, as well as a message in “full view”.
Comment 3 Joe Strzemp 2010-05-03 18:15:22 PDT
Problem still exists with r58691 for me.

An additional observation, though I'm not sure it's related to this problem:

The console reports an error that don't appear in the earlier version (r56855):

"Unsafe JavaScript attempt to access frame with URL http://us.mg2.mail.yahoo.com/dc/launch from frame with URL http://ad.doubleclick.net/... very long param list ...?. Domains, protocols and ports must match."

Seems like a security restriction that is now being triggered which may or may not be valid.
Comment 4 mitz 2010-05-03 18:26:19 PDT
Perhaps a screenshot, possibly annotated, will help me understand how to reproduce the problem.
Comment 5 Joe Strzemp 2010-05-03 21:43:54 PDT
mitz: Your testing was correct, so I don't think a screen shot will help.

I did some checking and found there's another requirement to see this problem.

This problem happens with Adobe Flash Player 10.1 RC2 installed or
Adobe's Flash Player "Gala" (H/W acceleration) Preview Release
(which Adobe's documentation says is based on 10.1 RC?).

(I was trying out the "Gala" h/w acceleration release days earlier and
hadn't made the connection to the problematic behavior prior.)

I do not see the problem with Adobe's Flash Player
(current production version).
Comment 6 mitz 2010-05-03 21:52:18 PDT
Thanks! I can reproduce with Flash 10,1,81,3 (the “Gala” preview).
Comment 7 mitz 2010-05-03 23:45:37 PDT
Created attachment 54999 [details]
Comment 8 mitz 2010-05-05 16:50:28 PDT
Created attachment 55175 [details]

This does not fix issues with scrolling PDF documents in iframes in composited layers. Includes a manual test. I don’t think an automated test is possible.
Comment 9 Simon Fraser (smfr) 2010-05-05 17:01:13 PDT
Comment on attachment 55175 [details]

r=me but can't we have a Layout Test that loads, waits for a draw, then scrolls, then is snapshotted?
Comment 10 mitz 2010-05-05 17:37:45 PDT
Fixed in <http://trac.webkit.org/projects/webkit/changeset/58847>.
Comment 11 WebKit Review Bot 2010-05-05 18:03:20 PDT
http://trac.webkit.org/changeset/58847 might have broken SnowLeopard Intel Release (Tests)