I speak from ignorance of FF3, being quite happy with FF2, but I wonder if it is the setting shown in the Tab Mix Plus add-on as Links | Open links from other applications in: | [New Window][New Tab][Current Tab] That will put something into about:config but I haven't been exploring, so can't say what. Thanks! North of Watford though its a very dynamic add-on sadly it didn't allow me to open an external link, I even tried upgrading to 3.6 from 3.5.11 to use another add-on called "Restore Open_External" and that failed :-( I have copies of the registry to compare the FF2 and FF3 installs and there's nothing there that would suggest anything either so now I am going to compare the .ini and .js files from each install i.e. the pref.js as seen in about:config to see what gives... lastly I will try the latest FF beta to see if that will help.