Hi, there are several ways to do this: Right click > Open Link In New Tab. Or click the mouse wheel. Or hold down Ctrl whilst left clicking.

There are also add-ons - Open Link in New Tab

And - Tab Mix Plus.

If your question is resolved by this or any other answer, please take a minute to let us know. Thank you.

Thanks for the response but the problem is I'm clicking on a link in an other application so I can't do the right click thing. The first add-on I tested before and it didn't work. I tried the Tab mix plus now though and there was a choice to always use only one window which seems to have solved my problem. Sometimes it's usefull to have another window though so I'm not sure if it's the perfect solution but maybe it will have to do :)

Ok I think I solved it now, seems the problem was the other application (in this instance mirc) was set to open all links in a new window. Found the setting to disable it and now I'm getting new tabs instead :)