louisstow/Crafty — comment on commit 56b238d2fa9b86fe25ca0eb3e214c3ec2eb972f5
File: src/storage.js line 359
By mpetrovic:

It's not a standard yet, it's still in Working Draft. But it's also something IE8 would never implement. That it would break is surprising, since reserved worlds are allowed object properties according to the ECMAScript standard.