[whatwg] .tags on HTMLCollections

[Boris Zbarsky]

Ian just pointed out to me that his current draft requires 
HTMLCollections to implement a tags() method (which seems to do a filter 
by tagName on the contents of the collection).

As far as I can tell, IE, Webkit, and Opera implement this; Gecko does 
not.  I was wondering whether any of the Webkit or Opera folks could 
comment on _why_ they implement this?  I haven't seen any uses of this 
in the wild (outside document.all.tags, but document.all doesn't behave 
like a normal HTMLCollection in all sorts of other ways either).

I'd rather be specifying (and implementing) a smaller DOM API, if that's 
all that's needed for actual web compat....

-Boris