Apparently, this problem was already known more than 4 months ago:

	https://bugzilla.mozilla.org/show_bug.cgi?id=924386#c19

I guess it specifically affect the mobile web? for it didn't prevent Firefox to ship `Array.prototype.entries` in v28, released on March 18.

—Claude

Le 17 juin 2014 à 01:08, Oliver Hunt <oliver at apple.com> a écrit :

> It turns out there are a number of sites (such as mobile.twitter.com) that are property detecting .entries on objects, and that means that they're breaking when Array.prototype.entries is provided.
> 
> We're removing it from JSC now, until we can find a way to expose it without causing site breakage, although this does seem like fixing it would require bringing back the awful "pretend that you're undefined" horror.
> 
> --Oliver
> 
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> es-discuss mailing list
> es-discuss at mozilla.org
> https://mail.mozilla.org/listinfo/es-discuss

Apparently, this problem was already known more than 4 months ago:

> https://bugzilla.mozilla.org/show_bug.cgi?id=924386#c19

I guess it specifically affect the mobile web? for it didn't prevent Firefox to ship `Array.prototype.entries` in v28, released on March 18.

—Claude