Unlock is a Firefox add-on designed to help users access articles that are typically hidden behind paywalls. This subscription-based tool redirects users to archived versions of articles from archive.today, enabling them to read content from popular publications without the usual restrictions. Currently, it supports several renowned sources including The New York Times, The Wall Street Journal, and Bloomberg.

The functionality of Unlock requires users to complete a Google reCAPTCHA, ensuring a level of verification during the process. If an article is not already archived, users may experience a brief wait as the system generates a new capture. Originally developed for personal use, this add-on adheres to Mozilla's guidelines for public distribution, providing a valuable resource for those seeking access to premium content.