Import old bookmarks to Firefox through the Import and Backup option in the Firefox settings. It works with any HTML file from Firefox or other Web browsers. Before the old bookmarks can be imported, they must first be exported into the required file type in order to be recognized by FirefoxContinue Reading
The Bookmark button looks like a small box with an arrow at the top and three lines in the middle. Find it next to the search bar at the top of the browser; it is also next to a star icon for bookmarking the current website. Click the Bookmark button to reveal several options.
After clicking the button, a window appears and shows various bookmark-related options. Click Show All Bookmarks at the bottom of the list. It opens a new window over the Web browser.
Click the Import & Backup button at the top of the page, and choose Import Bookmarks From HTML. A new window pops up. Navigate to the folder that contains the HTML file. Click the file, and click the Open button. Firefox then imports the bookmarks and lets you view them using the Bookmark button in the browser. Alternatively, view your bookmarks with the hotkeys "Ctrl+Shift+B", or check the option to view your bookmarks on a bar.