Uncaught TypeError: Cannot read property ‘top’

I keep getting this error in my javascript console in developer tools:
Uncaught TypeError: Cannot read property ‘top’ of undefined
at sticky_relocate (autoptimize_89b02278b0fbfb3b19e1bdf5785b65f9.js:115)
at HTMLDocument.<anonymous> (autoptimize_89b02278b0fbfb3b19e1bdf5785b65f9.js:116)
at i (jquery.js?ver=1.12.4:2)
at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4:2)
at Function.ready (jquery.js?ver=1.12.4:2)
at HTMLDocument.K (jquery.js?ver=1.12.4:2)

Not sure what this even means, any help would be appreciated

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