When a <code>javascript:</code> URL is drag and dropped by a user into the addressbar, the URL will be processed and executed. This allows for users to be socially engineered to execute an XSS attack on themselves. External Reference: https://www.mozilla.org/en-US/security/advisories/mfsa2017-11/#CVE-2017-5458 Acknowledgements: Name: the Mozilla project Upstream: Daniel Veditz