https://support.mozilla.org/en-US/kb/bookmarks-firefox
https://support.mozilla.org/en-US/kb/restore-previous-session
https://support.mozilla.org/en-US/kb/bookmark-folders-organize-your-bookmarks
https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer
https://support.mozilla.org/en-US/kb/import-bookmarks-html-file