Uncaught TypeError: Cannot read properties of undefined (reading ‘ready’)

Another issue here, there seems to be some kind of issue with some jQuery when Ajax is enabled…

Here’s the error in the browser console:

Uncaught TypeError: Cannot read properties of undefined (reading 'ready')
    at HTMLDocument.<anonymous> (frontend.js?ver=1.0.1:formatted:1074:53)
    at frontend.js?ver=1.0.1:formatted:550:19
    at e.exports (frontend.js?ver=1.0.1:formatted:237:135)
    at frontend.js?ver=1.0.1:formatted:546:13
    at Array.forEach (<anonymous>)
    at e.exports (frontend.js?ver=1.0.1:formatted:538:55)
    at h.afterAllSwitches (frontend.js?ver=1.0.1:formatted:390:13)
    at h.onSwitch (frontend.js?ver=1.0.1:formatted:329:57)
    at h.outerHTML (frontend.js?ver=1.0.1:formatted:454:18)
    at frontend.js?ver=1.0.1:formatted:924:13

Which is throwing an error on this this line of code:

var e = jQuery._data(document, "events").ready;

The page I need help with: [log in to see the link]