Someone requested this back in March but it was closed because it wasn’t described very well.
Tab Mix Plus is a very powerful tab management tool in Firebox. I have yet to find ANY web browser that can natively force a new tab to open for every kind of URL link, search bar query and URL bar entry. This is especially useful for research and keeping a tab trail of your research. ALL other browsers require someone to manually open a new tab before entering a new search, web address or requiring you to right click on a link to choose “Open in new tab.” This add-on automates all of that so you don’t accidentally lose a website before moving onto the next search.
This is indispensable for people who heavily research things all day long.