Firefox already allows exporting bookmarks, but it's all or nothing. Could we have the ability to export only selected bookmarks, including selected folders? And on reïmporting, duplicate detection and prompting the user about the duplicates.
Note: The imported bookmarks will be added to your existing bookmarks, which may result in duplicate bookmarks. You can delete unwanted Firefox bookmarks before importing a new set of bookmarks, but this can be time-consuming.