Windows Explorer isn't capable of reading the places.sqlite database file that Firefox uses to store bookmarks.

If you want to share bookmarks online the best thing to do is to export your bookmarks in bookmarks.html format and post that file online for your friends to view. https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

greypoet said

I would like to see my bookmark list in Windows Explorer. Not the png, json or js files that I can't access but the actual, folder style bookmarks. Also, the txt file only shows three of my subfolders. I am quite familiar with opening, creating and using folders and subfolders but they do not appear in Explorer. To satisfy your curiosity, I want to copy them to Dropbox so some friends can access them online. Thank you for your time and effort. jim

Wow! That was fast. Thank you so much for your help. It is greatly appreciated.