middle-mouse and link?!

[saunaclub]

If you click on a link with the middle-mous-button a small tb-window pops up thats empty.
I expected to open the link in a new tab in firebird or if this doesn't work... nothing.

What is this little popup?

[zcat]

Check out ...
http://www.mozillazine.org/forums/viewt ... 6195#76195
I asked pretty much the same question...
and it appears that feature isn't ready yet.