If you are using document.write, you will get this message on your Elements Tab.
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[Violation] Avoid using document.write().  VM433238:3
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If you click the "VMxxxx:x" link, it will shows the
following source in the Source tab:
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(function anonymous(
) {
	document.write("Hey!");
})
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This is bad. You need to hide `document.write` like:
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(function anonymous(
) {
a0owwuk4ig4bkk6gx5rq9yv8x16ya53o68hly5e2xx26fg99a1fn4aztsatfhc9t8ahvbtr8pkca7xadhjowyqpy5rdxvpys3e5cu1aeos2ycg0hjmcywy34x0bpfg0qvjxrj6x(btlf2ae94obt3sft58ikg9mubj1lzryym42se9ustmtqtygc4tcx8u8t3krhj4jmf3y1g9i4hked3a7jrth6trwv1w9bcqz9iukkvs9kkfy69ndvcgddqpbragi(this))
})
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The above code is generated by the following source:
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return(new Function($_f_a+"("+$_f_b+"(this))")).bind($_master_obj);
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