RESOLVED INVALID 26613
[Qt] Severe performance degradation when using "float:" CSS properties 
https://bugs.webkit.org/show_bug.cgi?id=26613
Summary [Qt] Severe performance degradation when using "float:" CSS properties
Gustavo Carvalho
Reported 2009-06-22 11:01:24 PDT
NOTE: I'm using Qt's main trunk version from their git repository (Not sure what webkit version it is). When I have over 100 DIV's, each with text and images, if a lot of the elements within those DIV's are positioned by using "float", selecting text can take up to 5 seconds. Removing the float property causes selection to be instantaneous, even with thousands of DIV's. A quick ( not very scientific ) test with Safari 3 and 4 revealed no such degradation. How to repoduce: Load a file with a few hundred DIV's. Each DIV should have a <p> with text and an <img> with a small image ( it can be the same in all DIV's). The <img> should have a class (Let's call it "testicon" ) In the CSS set ".texticon { float:left }". Load the file and try to select some text. I get a 3 to 5 second delay with 200 DIV's, on a black macbook. Removing the float restores the performance to the expected level, no degradation with up to thousands of DIV's.
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Simon Hausmann
Comment 1 2009-11-23 05:53:19 PST
Could you attach a testcase of yours that makes it easier for us to reproduce/verify this issue?
Kent Hansen
Comment 2 2010-03-12 02:54:02 PST
Closing this since we don't have a testcase.
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