Tell HN: CSS class selectors may become case (in)sensitive

1 points by jFriedensreich 1y ago ↗ HN

I discovered this behavior in chrome in an unfortunately long debugging session and maybe this saves someone time: When the encoding of a page is set to utf-8 in the http content type header, chrome treats css class selectors as case sensitive, but when utf-8 is declared in the !DOCTYPE header of the html file, they become case insensitive.

Curious if there is a back story of some spec that explains this or if this is just a random inconsistency

1 comment

[ 3.3 ms ] story [ 15.9 ms ] thread

bhaney 1y ago ↗

Class names are considered case sensitive in HTML, and CSS selectors honor this except when in quirks mode. I suspect you're activating quirks mode when you mess with the doctype, causing the matching behavior to become case insensitive. This should be the same in Firefox as well, but I haven't tested it.