Undo Closed Tabs Button is a Firefox add-on that significantly improves tab management by allowing users to easily reopen closed tabs. It features a user-friendly toolbar popup that lists recently closed tabs, making it simple to restore browsing sessions. By default, the add-on displays the last 25 closed items, but users can customize this limit according to their preferences through the options page. Each entry is clearly marked with the tab's title and fav-icon, facilitating quick identification of pages.

In addition to individual tab restoration, the add-on also provides a functionality to reopen all closed tabs simultaneously, enhancing browsing efficiency. This subscription-based tool is particularly beneficial for users who frequently manage multiple tabs, offering a streamlined process for organizing and accessing their web sessions.