The syntax of the above JS function also supports a parameter 'status=no' to switch of the status-bar, but this is ignored by Firefox. Actually, whatever the parameters for the new window are, Firefox will recognize the "intention" of opening a new window and will then do it using its own parameters: the location bar will always be visible, but grayed-out (read-only, which is very sensible in general, but not so much for my applications), and the status bar will be just as in the current setting (menu) "View - Status bar". Since the menu is disabled in the new window, I have to disable the status bar manually in my "web application launcher" window and then click on the link, which gives me a new window without status bar. The same is true for the location bar. I have to disable it manually before I click on the JS link. This is more complicated than it should be!
Best would really be to let me disable the menubar manually, too, and then have the browser simply remember the setting of status/menu/location bar for each website where I actively changed it. Being at it once, it should also remember the window size and position for each website where I manually change it.
There is also a terribly nasty bug: When I open Facebook in this way without a menu bar (no matter what the settings for status and location bar), it will open without scroll bars, but GMail with the same settings has scrollbars! Fortunately I could fix it by adding "scrollbars=yes" to the window.open() call. Just perplexing that GMail does not need it.