Blinkin' Firefox
Firefox supports the BLINK element. I can't believe it. For the love of the children, why?
For those of you who don't know, and can't guess, the BLINK element makes the text within it flash on and off in a distracting manner. Not nice, is it? (Obviously, you must be using a browser that supports the element to witness the effect.)
And there's worse to come! The blink value of the text-decoration property is part of the W3C draft CSS2.1 specification. However, the specification does go on to state that “Conforming user agents may simply not blink the text”, and “not blinking the text is one technique to satisfy checkpoint 3.3 of WAI-UAAG”. So support for this value is not necessary for a user agent to be in conformance with the standard, and its use may harm accessibility of your pages.
The BLINK element is not part of the (X)HTML standard, and pages using it will not validate. This page, for example, is the only one on this site that I'm aware of that does not, and will never, validate, because the BLINK element is used above.
So what's the point in introducing blinking text, which hinders accessibility and readability, to a CSS standard, and non-standard HTML tags to a ‘standards-compliant’ browser?
It has never been supported in Internet Explorer, and is not supported in Safari. Netscape Navigator dropped support in v6, although bizarrely enough it seems to have been reintroduced in v7. Opera and iCab can also hang their heads in shame.
In Dynamic HTML: The Definitive Reference (O'Reilly), Danny Goodman claims that the BLINK element—and, presumably, it's half-witted CSS descendent—is “Marc Andreessen's contribution to horrifying web pages”. He goes on: “Please don't use this tag. I beg you.”
All of which begs the question as to what on earth were the W3C smoking at the time?
And, as for Firefox, bad dog!