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• Import Bookmarks and other data from Microsoft Edge
  ( or favourites as us Brits tend prefer to spell favorites )

if you successfully followed those steps you should have the favourites available, as a folder within your bookmarks. You could always try exporting the IE bookmarks, and importing them again into firefox.

You can usually find the imported IE Favorites in a folder ("From Internet Explorer") at the bottom of the Bookmarks Menu folder (Bookmarks > Organize Bookmarks).

If you can't find them in the "From Internet Explorer" folder then try this:

• Export the favorites in IE to an HTML file (bookmarks.html): File > Import and Export
• Import the HTML file in Firefox: Bookmarks > Organize Bookmarks > Import & Backup > Import HTML: From File

See also:

• http://kb.mozillazine.org/Import_bookmarks ("Import from another browser" and "Import from file")