Uncaught TypeError: Cannot read property 'prototype' of undefined

Don't think we can read minds or do astral projections to see your monitor. If you need help, the least you could do is to add some relevant code to your question or to explain your problem in such a way, that the users of CP can understand it. Otherwise, nobody will be able to help you.

Please use the "improve question" and add relevant information or a piece of code envolved. There are thousands of ways to screw things up, how are we supposed to know which one did you choose?

Following links might help you understand what I mean and to improve the question so that you get the help you need:
What have you tried?[^]
How to ask a question?[^]
best way to post code snippets[^]