Uncaught TypeError: $(...).size is not a function

Uncaught TypeError: $(...).size is not a function

의 내용은 해당 jquery 버전에 삭제된 function 이다, 없는 놈을 호출하려니 에러가난다.

size() ==> length 로 바뀌었다. 

Check your version of jQuery. I was using the latest(3.1.1) some plugins i use were throwing this error.

according to the docs: The .size() method is deprecated as of jQuery 1.8. Use the .length property instead.

( it was removed in 3.0 )

so a simple rollback to a version before 3.0 did the trick.

edit: whoops, as A. Wolff says in the comments.