You can see the problem in action on http://www.meyerweb.com/ by selecting the presentation choice "natural" and allowing the cookie to be set. (If you want to delete it after testing, the name is 'meyerweb-style'.) The site's "masthead" doesn't take on the green background and butterfly image that it should. The problem seems to center around styling the same element multiple times using different stylesheets. I will attach a reduced testcase demonstrating that this is (apparently) confined to background styles and not others.
Created attachment 68339 [details] Reduced testcase (based on meyerweb.com) Note that the font-family and color are set by the second stylesheet in the source, just as they should be, but the background styles are ignored. This happens on meyerweb.com with LINKed external stylesheets, and here the stylesheets are embedded in the HEAD element. The behavior is the same either way.
I looked at the code and I didn't see anything obviously wrong with 'background-color' except that we don't do 'background-color: inherit' properly -- we treat it tas transparent. Is this only a problem with 'background-color', or other things? (I can't look at the testcase right now...)
This is a parsing problem. We're ignoring that 'background' line for some reason. If I take out the 'center right' it works.
I filed bug 124219 on the other issue I noticed.
The problem seems to be that 'center right' and 'center left' values for 'background-position' don't seem to parse within the shorthand. 'center top' and 'center bottom' seem to work OK. I didn't try very much else.
Created attachment 68359 [details] simpler testcase
Verifying that 'center top' and 'center bottom' are fine. I also tried 'left center' and 'right center' and they were okay. It would seem that any time 'center' comes before the either one of the keywords 'right' or 'left', Mozilla gets confused.
Created attachment 68369 [details] Stepping through background-position keyword combinations
Created attachment 68371 [details] Stepping through background-position keyword combinations This testcase shows all of the various combinations for position keywords. Green backgrounds showing an image are okay. Red backgrounds with no image fail.
We have eCSSProperty_background_x_position coming before eCSSProperty_background_y_position in the kBackgroundIDs list in ParseBackground. So when parsing this shorthand we try the x-position parser on "center" and it works. So we say that x-position is center. Then we try to parse "right" and parse y-position as "right". Now we go back to ParseBackground and start validating the values. x-position is "really an X value", so we check the y value which is _not_ really a y-value, and then we fail. The validation logic needs to handle this case.
Comment on attachment 68377 [details] [diff] [review] Proposed patch r=pierre
Comment on attachment 68377 [details] [diff] [review] Proposed patch sr=attinasi
a=roc+moz for 0.9.9
->bzbarsky, so he doesn't forget to land it :-)
I assume the patch will also fix this problem in 'background-position' , which suffer the same problem? The patch appears to do so but I wanted to make double-sure.
Checked in on trunk (pre-branch).
erm, actually I'm pretty sure this does not fix any problems there may be with background-position. Eric, could you file a bug on me on that? (if you have a testcase that would be great too).
Just looked at the code for background-position. It's correct. I also modified the testcase in this bug to use background-position and we passed. So no new bug needed that I can see. :)