Multi URL Opener is a Firefox add-on designed to streamline the process of opening multiple URLs simultaneously. This subscription-based tool allows users to create personalized sets of their favorite websites, making it easy to access frequently visited pages without repetitive clicks. Users can name their sets and add multiple URLs, which can be managed effortlessly. The add-on features a simple interface with an attention-grabbing orange button that triggers the opening of all URLs in a selected set, enhancing browsing efficiency.

The functionality of Multi URL Opener extends beyond just opening sets. Users can edit, sort, and delete URLs within a set, as well as manage entire sets themselves. This flexibility allows for a customized browsing experience tailored to individual needs. Overall, Multi URL Opener provides a practical solution for those who regularly visit several websites, saving time and effort in daily internet navigation.