Web Pages Scanner is a free Firefox extension designed to monitor changes on web pages. It allows users to scan an unlimited number of pages, offering both automatic and manual scanning options. Key features include the ability to modify charset settings, adjust scanning accuracy, and set intervals between scans. Users will receive notifications whenever detected changes occur, and there is an easy option to add pages to the scan list. The extension also provides a preview of both old and new versions of the monitored pages, enhancing the user's ability to track updates effectively.

The extension is compatible with Firefox 54 and later, featuring a convenient sidebar for easy access. Although it boasts an extensive range of functionalities, some users may encounter difficulties adding pages when tracking protection is enabled. Overall, Web Pages Scanner is a robust tool for anyone looking to keep track of changes on their favorite websites.