A: Absolutely. Unofficial mirrors are not bound by AO3’s strict content security policies. They can host pop-under ads and malicious scripts.
However, as long as fanfiction remains a target for censorship and server attacks, the chase for mirrors will continue. Q: Is it illegal to use an AO3 mirror? A: In most jurisdictions, viewing a website is not illegal. However, scraping and rehosting (creating the mirror) violates AO3’s terms of service and potentially copyright law regarding the specific fanworks. ao3 mirror link
However, there is a critical distinction to make here: A: Absolutely
While that specific mirror is gone, others pop up regularly. Just because a mirror works doesn't mean it is ethical. If you have read the risks and still want to find a working link, user communities are your best bet. However, note that due to the transient nature of these mirrors (they get shut down or go private), I cannot provide a specific working URL here , as they change daily. However, as long as fanfiction remains a target