Rating:

Purify documents to be unsafe for use in jquery's .html() in their README if SAFE_FOR_JQUERY is not set (which is not).
Searching for the variable in the source code reveals test code for the scenario:
https://github.com/cure53/DOMPurify/blob/2724763e41313b1a54724dfda5573e8b63116962/test/test-suite.js#L53

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