Selectnav is not defined

Hi

I have inherited a client with a bloated site using Food and Cook theme. I have already tidied up and thrown out what I dare, but notice that responsive mobile menus no longer work (“Navigation” appears but clicking on it achieves nothing).

In Dev Tools (Chrome) I can see:

plugins.js?ver=4.9.1:11 Uncaught ReferenceError: selectnav is not defined
    at HTMLDocument.<anonymous> (https://www.thematchagreen.com/wp-content/themes/food-cook/includes/assets/js/plugins.js?ver=4.9.1:11:3)
    at i (https://www.thematchagreen.com/wp-includes/js/jquery/jquery.js?ver=1.12.4:2:27449)
    at Object.fireWith [as resolveWith] (https://www.thematchagreen.com/wp-includes/js/jquery/jquery.js?ver=1.12.4:2:28213)
    at Function.ready (https://www.thematchagreen.com/wp-includes/js/jquery/jquery.js?ver=1.12.4:2:30006)
    at HTMLDocument.K (https://www.thematchagreen.com/wp-includes/js/jquery/jquery.js?ver=1.12.4:2:30368)
    at <anonymous>:2:479
    at HTMLDocument.f.string.e.function.b.(anonymous function) (eval at exec_fn (:2:27), <anonymous>:52:92)
    at <anonymous>:2:479
    at c (<anonymous>:2:324)
    at <anonymous>:2:479
(anonymous) @ plugins.js?ver=4.9.1:11
i @ jquery.js?ver=1.12.4:2
fireWith @ jquery.js?ver=1.12.4:2
ready @ jquery.js?ver=1.12.4:2
K @ jquery.js?ver=1.12.4:2
(anonymous) @ VM2349:2
f.string.e.function.b.(anonymous function) @ VM2372:52
(anonymous) @ VM2349:2
c @ VM2349:2
(anonymous) @ VM2349:2
ea @ VM2372:52
l @ VM2372:49

I can see both plugins.js and selectnav.min.js in the js directory, but the way this theme loads stuff is opaque! Am also not thrilled that it’s using such an old version of jquery, but that’s a minor issue.

Any ideas out there?

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