console.log(new Array(16).join("wat"-1) + " Batman!")

Opened Web Inspector in Safari and pasted the above. (I knew what to expect but did not know how it would work … me trying to figure out what subtracting 1 from a string (ASCII?) would give you. But very related to this post.)

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Indeed, this shtick was funnier 13 years ago. https://www.destroyallsoftware.com/talks/wat

JavaScript is a quirky, badly-designed language and I think that is common knowledge at this point.