Per http://dev.w3.org/csswg/css3-background/#the-border-image , when the border-image property has fewer than 4 offset values, the left value (4th) is supposed to get the same value as the right (just like for CSS box properties). In WebKit SVN r34192, when three values are specified, the missing left value is filled in using the value from the top (1st) instead of the value from the right (2nd). Steps to reproduce: load attached testcase. Note that the image is random so the pixel grid is clearly visible. Expected results: left border has two image pixels in it Actual results: left border has one image pixel in it
Created attachment 21406 [details] testcase
Created attachment 21420 [details] Will land testcase from bug
Comment on attachment 21420 [details] Will land testcase from bug r=me, assuming a good ChangeLog and test case I'd prefer a text-only test case if possible, too.
Good point. There is no reason to make a graphical test case here.
Fixed in r34324.