(Ah - I put in some analysis into the diagnostic text box when submitting, but that doesn't get shown here...)

Basically, if I embed javascript to open a URL with "window.open(url,id)", then it works properly, but if I set some attributes like window position and size and open the URL with "window.open(url,id,attributes)", then it exhibits the errant behaviour.

My previous code was "window.open(url,id,"width=w,height=h,left=x,top=y)", and my workaround is to do "mywin = window.open(url,id)", and then "mywin.moveTo(x,y)", followed by "mywin.resizeTo(w,h)".

See:

• http://kb.mozillazine.org/browser.link.open_newwindow.restriction

Thanks - I've tried the permutations on browser.link.open_newwindow and browser.link.open_newwindow.restriction, but there doesn't seem to be one that matches the old behaviour.

Option 2 says:

"Divert all links according to browser.link.open_newwindow, unless the new window specifies how it should be displayed. (Default in Firefox 1.5 and later, in SeaMonkey 2.1a3 and later, and Camino 1.5)

This includes:

   All links with target="_blank".
   JavaScript calls to window.open() without the "features" parameter (3rd parameter). 

This does not include:

   JavaScript calls to window.open() with the "features" parameter (3rd parameter). 

I think the old behaviour may have included window.open() with the features parameter.

Would it be possible to get an option 3 in there to allow that too?

You may be seeing this bug.

• bug 644729 - Popup window with all toolbars visible causes new tabs to open in another browser window

(please do not comment in bug reports; you can vote instead)

Yes - that is similar to the behaviour I am seeing (I have my tabs visible in all windows, as per the bug report, and also the address bar).

But it brings the parent window to the foreground when it opens the tab there.

It happens with windows opened from javascript window.open() with the features parameter specified.