URL: https://www.kayak.com/
Browser / Version: Firefox 48.0
Operating System: Mac OS X 10.11
Problem type: Something else - I'll add details below

Steps to Reproduce
Site is borked.

TypeError: a.unshift is not a functionglobalalien.js:34:19732
TypeError: f.shift is not a functionhorizon.js:1:151
TypeError: b.define is not a functioncommon.js:1:16
TypeError: b.createComponentClass is not a functionhotels.js:1:16
TypeError: b.createComponentClass is not a functionbase.js:1:16
TypeError: b.createComponentClass is not a functionmarketing.js:1:16
TypeError: b.createComponentClass is not a functionseo.js:1:16
TypeError: R9.ajax is undefined

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