[H3RR3S]

I get following error in my console when I try to open my drop down menu on my forum.

Code:

jquery.js?ver=1813:2 Uncaught Error: Syntax error, unrecognized expression: jquery.js?ver=1813:2 #
    at Function.ga.error (jquery.js?ver=1813:2)
    at ga.tokenize (jquery.js?ver=1813:2)
    at ga.select (jquery.js?ver=1813:2)
    at Function.ga [as find] (jquery.js?ver=1813:2)
    at r.fn.init.find (jquery.js?ver=1813:2)
    at new r.fn.init (jquery.js?ver=1813:2)
    at r (jquery.js?ver=1813:2)
    at b (bootstrap.min.js:6)
    at HTMLAnchorElement.g.toggle (bootstrap.min.js:6)
    at HTMLDocument.dispatch (jquery.js?ver=1813:3)