This is the error i get in all browsers.
File not found
Firefox can't find the file at https://nsnbc.wordpress.com/wp-admin/export.php?download=true&content=all&cat=0&post_author=0&post_start_date=0&post_end_date=0&post_status=0&page_author=0&page_start_date=0&page_end_date=0&page_status=0&submit=Download+Export+File.
Check the file name for capitalization or other typing errors.
Check to see if the file was moved, renamed or deleted.