Uncaught DOMException: Failed to execute ‘querySelectorAll’ on ‘Document’

The “sticky menu” on our site is no longer appearing. Looking in the JavaScript console, I see this error:

Uncaught DOMException: Failed to execute 'querySelectorAll' on 'Document': '[object Object]' is not a valid selector.

at r )

at Swiper.i.createPagination )

at et )

at new Swiper )

at HTMLDivElement.<anonymous> )

at Function.each )

at s.fn.init.each )

at i )

at 

at dispatch )

If I disable the “Shortcodes Ultimate” (v5.12.5) plugin, this error and the “sticky menu” problem go away.

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