Integrates Well Rated 5 out of 5 stars

This add-on modifies the General tab of Firefox Options to include the "Preserve..." checkbox in the Downloads section. Because this is redundant of the same checkbox appearing in the add-on's own Options dialog, I jumped to the conclusion that Firefox had added the same capability in the base browser, but that's not the case (at least not as of FF 8.0) so this add-on remains a must-have for me.