The 'Add Search Engine from Mycroft Project' is a Firefox extension designed to facilitate the installation of search engines that were previously compatible with the Mycroft Project. Due to changes in Firefox 65, which removed support for the non-standard feature used by Mycroft, this extension provides a necessary workaround. Users can easily add search engines by clicking on a search engine link from Mycroft Project, which directs them to an installation page.

Upon reaching the installation page, users can initiate the addition of the search engine by accessing the menu in the address bar and selecting 'Add Search Engine.' This straightforward process ensures that users can continue to customize their search experience in Firefox, despite the recent limitations imposed by the browser's updates.