At some point in my CSS research, I came across a bug report about the fact that Firefox doesn’t support the invert keyword for the outline-color property. One user said the following in the thread:
“Let me point out that ‘outline-color:invert’ is part of the CSS 2, CSS 2.1 and CSS 3 specs, so it’s not just a matter of taste. If you want a conformant user agent, you have to implement inversion. Period.”
I can certainly see where this person is coming from. But I’ve learned that things aren’t so simple in vendor/implementor land. In fact, one of the responses is from Vladimir Vukicevic, a Mozilla engineer, and he explains:
“It’s all only software; so sure, you could always write code that could do invert. Now, is it worth taking the tradeoffs that would allow us to support invert, that is losing access to hardware acceleration and other advantages? The answer to that is no.”
Vladimir gives a few more details on the problem and then gives his vote for WONTFIX (which is where the bug stands today). In fact, as pointed out later in the thread, the spec now includes a note that support in browsers is optional.
So next time you think one of the big browsers should ‘get their act together and support feature x’, remember that sometimes there’s a lot of stuff going on behind the scenes that holds back this kind of thing from moving forward as quickly as we would like.
This editorial appears in this week’s issue of the SitePoint Front-end Newsletter.