UnMHT allows you to view MHT (MHTML) web archive format files, and save
complete web pages, including text and graphics, into a single MHT file in
Firefox/Mozilla Suite. With UnMHT installed you can click on a web page link
to a ".mht" file and it will open correctly in Firefox (depending on the
speed of your connection/system it may take a second for Firefox to reload
the page). (in Internet)