31630 2009-11-18 09:47:46 -0800 Avoid downloading CSS background images that will never be visible 2010-02-14 14:26:42 -0800 1 1 1 Unclassified WebKit CSS 528+ (Nightly build) All All RESOLVED DUPLICATE 24223 HasReduction P2 Normal --- 1 rik webkit-unassigned darin hugues.lismonde hyatt laszlo.gombos martinklepsch mitz simon.fraser oldest_to_newest 164606 0 43437 rik 2009-11-18 09:47:46 -0800 Created attachment 43437 Testcase 1. Open the attached testcase 2. Check in the Resources panel or in the Activity window Actual result: The image was downloaded Expected result: The image wasn't downloaded Without this behavior, the CSS gradients are less useful since you still download a useless image. Firefox3.6beta3 is not downloading the image. 165032 1 darin 2009-11-19 11:24:17 -0800 Hyatt has long been our "what images need to be loaded" strategist. In general there are images and stylesheets and other objects you might wish to not load that need to be loaded to support "preloading" behavior expected by websites or other correctness issues. But obviously, not loading things is *way* better for performance. Hyatt, can you weigh in on this? 167733 2 44099 martinklepsch 2009-12-01 13:56:34 -0800 Created attachment 44099 Shows how an with "! important" overwritten image gets loaded. when forcing backgound-image: none; with !important any background-image declaration after that one should be ignored therfore the images should not get downloaded to the client. 167737 3 44100 martinklepsch 2009-12-01 14:09:39 -0800 Created attachment 44100 Shows how an regulary overwritten image gets loaded. this shows that images that are overwritten simply by a second background assignment are also loaded. 167743 4 martinklepsch 2009-12-01 14:18:09 -0800 (In reply to comment #1) > Hyatt has long been our "what images need to be loaded" strategist. In general > there are images and stylesheets and other objects you might wish to not load > that need to be loaded to support "preloading" behavior expected by websites or > other correctness issues. But obviously, not loading things is *way* better for > performance. > > Hyatt, can you weigh in on this? i think it's okay to load images that are just not visible at the beginning (icons for js flash messages for example) but loading images that are overwritten by another property declaration is unneeded. maybe i'm wrong but i've never seen something like this in js: removing a second property declaration in order to make the first declaration used by the browser to render the page. 186558 5 hugues.lismonde 2010-02-01 13:48:15 -0800 I'll vote for this one too. Overridden background-image should never be downloaded, as Anthony said, it defeats the purpose of using graceful degradation with gradients, shadows, ... (but "invisible" background images should definitively be downloaded/prefetched). 190352 6 hyatt 2010-02-14 14:24:54 -0800 Yes, this is just a bug. I think it's already been filed. 190353 7 hyatt 2010-02-14 14:26:42 -0800 *** This bug has been marked as a duplicate of bug 24223 *** 43437 2009-11-18 09:47:46 -0800 2009-11-18 09:47:46 -0800 Testcase gradient.html text/html 302 rik PCFkb2N0eXBlIGh0bWw+CjxzdHlsZT4KYm9keSB7CiAgICBoZWlnaHQ6IDQwMHB4OwogICAgYmFj a2dyb3VuZDogdXJsKGh0dHA6Ly93ZWJraXQub3JnL2ltYWdlcy9ncmVlbi1iYWNrZ3JvdW5kLnBu Zyk7CiAgICBiYWNrZ3JvdW5kOiAtd2Via2l0LWdyYWRpZW50KGxpbmVhciwgbGVmdCB0b3AsIGxl ZnQgYm90dG9tLCBmcm9tKCMyODEpLCB0byh3aGl0ZSkpIG5vLXJlcGVhdDsKICAgIGJhY2tncm91 bmQ6IC1tb3otbGluZWFyLWdyYWRpZW50KCMyODEsIHdoaXRlKSBuby1yZXBlYXQ7Cn0KPC9zdHls ZT4KPGJvZHk+PC9ib2R5Pgo= 44099 2009-12-01 13:56:34 -0800 2009-12-01 13:56:34 -0800 Shows how an with "! important" overwritten image gets loaded. url.txt text/plain 45 martinklepsch aHR0cDovL2V4cGVyaW1lbnRzLm1hcnRpLmluL3JnYmFfcGVyZm9ybWFuY2Uv 44100 2009-12-01 14:09:39 -0800 2009-12-01 14:09:39 -0800 Shows how an regulary overwritten image gets loaded. url.txt text/plain 66 martinklepsch aHR0cDovL2V4cGVyaW1lbnRzLm1hcnRpLmluL3JnYmFfcGVyZm9ybWFuY2UvcmVndWxhck92ZXJ3 cml0ZS5odG1s