Been using Firefox for decades, and there is a recent change which has me flummuxed. I've gone to a dual boot Windows system and want to export my bookmarks from one Firefox to the other. I go to All Bookmarks/Import and Backup/ and see a button that says "save in html", just as in former versions. I click on "Save to HTML" and tell it to go to my usual Firefox backup place in which I have backups going back to 2014 in html, the last dating to August or September 2018. Click "save". I then click on "Import from HTML". My newest backup shows in .json but NOT in HTML. What am I doing wrong?