Created attachment 8759493 [details] testcase This bug is a following bug from bug 1275957 comment 14. While the background-size is 33% auto, gecko takes it as 33% 100% and other browsers use 33% 33%.
https://drafts.csswg.org/css-backgrounds-3/#the-background-size says: > An ‘auto’ value for one dimension is resolved by using the > image's intrinsic ratio and the size of the other dimension, > or failing that, using the image's intrinsic size, or failing > that, treating it as 100%. So per the spec, our behavior is correct, since a gradient has neither an intrinsic size nor an intrinsic ratio, per https://drafts.csswg.org/css-images/#gradients which says: > However, the gradient itself has no intrinsic dimensions. where "intrinsic dimensions" is a link pointing to: > The term intrinsic dimensions refers to the set of the > intrinsic height, intrinsic width, and intrinsic aspect > ratio (the ratio between the width and height), each of > which may or may not exist for a given object. [...]
Given that both Chromium and Edge get this wrong, it's probably worth bringing up on www-style. (Also worth testing WebKit, though.)
You need to log in before you can comment on or make changes to this bug.