Notes about the FRI file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The FRI file type is primarily associated with 'Firefox'. Produced by a Firefox extension that creates a bookmark backup file each time you close the Firefox browser. If your bookmark file is called BOOKMARK.HTML then the backup will be BOOKMARK.HTML.FRI on a Friday.