Show tabs like a tree.
Allows URI texts written in webpages to be loaded by double clicks.
After you installed this addon to your Firefox, bookmarks are opened in new tab always. This project seems needless on Firefox 57 and later. You just go to "about:config" and turn "browser.tabs.loadBookmarksInTabs" to "true".
Applies "Tabs on Bottom" appearance.
Provides feature to close multiple tabs.
Opens new tabs from the location bar, by conditions.
Loads links in new tabs, by conditions.
Suspends background old tabs automatically to save memory usage.
Popups alternate texts of images or others like NetscapeCommunicator(Navigator) 4.x.
This provides separated "Bookmarks" Sidebar panel like Opera.