jQuery UI slider - Cannot call method 'addClass' of undefined

Question

I had this old jQuery UI slider that had worked just fine a few months ago, but now I seem to be getting an exception reading: Cannot call method \'addClass\' of undefined.

Answer 1

For anyone reading back on this question, if you're pulling from a CDN, try pulling from the latest jQuery UI version. I also got this problem, and it was solved by using a later jQuery UI version.