Re: [csswg-drafts] [css-backgrounds] background-size: cover spec seems to not reflect implementations (#4049)

> I'd say that this—not drawing a cover-sized image if one dimension of the reference box is 0—is a Firefox bug. (Sorry.)

No need to be sorry. To be clear I agree with this and the bug is fixed already. What I don't understand (and this may be me not properly understanding something subtle of the spec sentence) is what makes my first example any different from:

```html
<!doctype html>
<style>
body { margin: 0 }
.test {
  background-size: cover;
  background-repeat: no-repeat;
  background-position: top left;
  background-origin: content-box;
  /* 2x1 red background */
  background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAA+gAAAH0AQMAAACU5pVuAAAAA1BMVEX/IyMFLA8kAAAAVElEQVR42u3BMQEAAADCoPVPbQZ/oAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA+A/YYAAHqybvmAAAAAElFTkSuQmCC);
  width: 0;
  height: 100px;
  padding-left: 100px;
}
</style>
<div class="test"></div>
```

Which all browsers agree to render blank. The only difference here is which axis of the positioning area is zero.

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Received on Saturday, 22 June 2019 10:15:06 UTC