Then I tested it in Safari. Two weeks later I gave up and basically had to `if (Safari)`. I don't know if the code still has that, but it probably does. This wasn't anything 'lacking'. Sure, it was contenteditable-related but the fact remains that I found a consistent subset in every browser except Safari.
So, yes, Safari broke my web - and it wasn't something that was missing, it was something that behaved very differently compared to other browsers. I can't remember what specifically broke it, but even ~2 years ago I had a significantly better development experience with IE than Safari with no new HTML5 features in sight.
[1]: http://help.k2.com/onlinehelp/k2smartforms/userguide/1.0.6/c...