There are now a couple of security spoofs out there for Mozilla Firefox. Unlike IE there is an easy way to catch them that is not often mentioned.

Simply type in about:config into the address bar, then search for and change these settings to true:

recommended:

dom.disable_window_open_feature.location
dom.disable_window_open_feature.status
dom.disable_window_open_feature.titlebar
dom.disable_window_status_change

optional:

dom.disable_window_move_resize
  [good against user-initiated popups]
dom.disable_window_open_feature.close
dom.disable_window_open_feature.directories
dom.disable_window_open_feature.menubar
dom.disable_window_open_feature.minimizable
dom.disable_window_open_feature.personalbar
dom.disable_window_open_feature.resizable
  [handy against those tiny non-resizable popups too]
dom.disable_window_open_feature.scrollbars
dom.disable_window_open_feature.toolbar

Hope anybody thinks this useful. Of course, check out the "Web Features" settings dialog out first.