Bug 44529 - beforeload listener causes rendering flash
Summary: beforeload listener causes rendering flash
Status: UNCONFIRMED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Layout and Rendering (show other bugs)
Version: 528+ (Nightly build)
Hardware: Mac (Intel) OS X 10.6
: P2 Normal
Assignee: Nobody
URL: http://cbgb.com/
Keywords:
Depends on:
Blocks:
 
Reported: 2010-08-24 09:29 PDT by Drew Thaler
Modified: 2010-09-07 12:34 PDT (History)
3 users (show)

See Also:


Attachments
screenshots and extension (2.12 MB, application/zip)
2010-08-24 09:29 PDT, Drew Thaler
no flags Details

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Description Drew Thaler 2010-08-24 09:29:05 PDT
Created attachment 65283 [details]
screenshots and extension

A highly reproducible rendering flash occurs on http://cbgb.com/ whenever a Safari extension adds a 'beforeload' listener to the page. It doesn't matter what's in the listener; the problem can be reproduced with a trivial empty listener. Removing the listener eliminates the problem.

The site is using jShowoff to rotate through different header images every 8 seconds or so. The initial load of the page is OK, but almost every time the header rotates after that, it will render incorrectly for a fraction of a second as it changes to the next image.

The attached zip includes:
 - header-good.png = screenshot of correct rendering
 - header-bad.png = screenshot of incorrect rendering
 - beforeload.safariextension = source of Safari extension to reproduce the problem
 - beforeload.safariextz = packaged Safari extension to reproduce the problem
Comment 1 Drew Thaler 2010-08-24 09:31:20 PDT
Sorry, I should've mentioned the versions. I've reproduced it on both Safari 5.0.1 and WebKit Nightly r65825.
Comment 2 Alexey Proskuryakov 2010-09-07 12:34:58 PDT
See also: bug 45225.