jiggliemon/polyfills — comment on commit a8e9ec084077fe9d05f923aa981d2057aa3dd08f
File: Array/Array.isArray.js line 10
By jiggliemon:

They've since updated theirs as well. I think in reference to : http://perfectionkills.com/instanceof-considered-harmful-or-how-to-write-a-robust-isarray/