Bug 12206
| Summary: | REGRESSION: FOUC posting to blog | ||
|---|---|---|---|
| Product: | WebKit | Reporter: | David Kilzer (:ddkilzer) <ddkilzer> |
| Component: | Layout and Rendering | Assignee: | Nobody <webkit-unassigned> |
| Status: | RESOLVED CONFIGURATION CHANGED | ||
| Severity: | Normal | CC: | frances_c, hyatt, karlcow, mitz, mrowe |
| Priority: | P2 | Keywords: | InRadar, Regression |
| Version: | 420+ | ||
| Hardware: | Mac | ||
| OS: | OS X 10.4 | ||
| URL: | http://mspong.com/ | ||
David Kilzer (:ddkilzer)
Summary:
Seeing FOUC (flash of unstyled content) when I post a comment to a blog entry on mspong.com.
Steps to reproduce:
1. Open Safari.
2. Load a blog entry like this one: http://mspong.com/2007/01/09/safari-compatibility/
3. Post a comment.
Expected results:
Comment should be posted with no FOUC.
Actual results:
Comment posted with FOUC.
Regression:
bdash says, via IRC, that the FOUC isn't as bad in shipping Safari, hence a regression.
Notes:
Tested with a locally-built debug build of WebKit r18738 with Safari 2.0.4 (419.3) on Mac OS X 10.4.8 (8L127).
FOUC seems worse on a slow connection.
| Attachments | ||
|---|---|---|
| Add attachment proposed patch, testcase, etc. |
Maciej Stachowiak
<rdar://problem/4960661>
Dave Hyatt
I am downgrading the severity of this regression after studying the page.
Here is what's happening:
(1) In the <head>, a script writes an <img> This forces the early creation of a <body> and a renderer.
(2) The Web page even paints. This <img> is width/height of 0, so nothing shows up.
(3) The stylesheets are then encountered. We do not allow FOUC suppression after the body has a renderer (meaning painting has happened), and so we FOUC.
This is a regression because shipping Safari would allow re-suppression during recalcStyle and would actually destroy renderers. This caused lots of bad bugs like links disappearing during loading. The current behavior is much better.
It is very hard to fix this bug I think without detecting that "nothing of substance" was painted.
Frances Cornwall
This domain does not exist anymore, but I was able to find this page using the wayback machine at: https://web.archive.org/web/20070323224418/http://mspong.com/2007/01/09/safari-compatibility/.
When trying to submit a post using the wayback machine, the page is all white/blank.
I don't think we can reproduce this bug anymore.
Tested on Safari 17.4.1.