Open new browser windows in JavaScript without making it active

Question

I have some JavaScript that makes an AJAX call and, if the call fails, opens a new windows (tab in Firefox) and displays the response from the server in that window. This is very convenient for debugging, because the error is typically from Pylons, so it's a full HTML page.

The only problem is that the new tab becomes the active tab, which would totally confuse a regular user. Is there any way to open the tab/window, but not make it active, ie. keep the current active window?

My code currently looks like this:

 errorWindow = window.open("", "TCerrorWindow")
 if (errorWindow)
  errorWindow.document.write(xhr.responseText);

Answer 1

AFAIK this is not possible, as a security measure against pop-under windows. For debugging purposes you could

• use Firebug (with a handy console, where you can output your own log messages from the code)
• create a debug layer (div) on your page, where you output error messages in case an error happens

Answer 2

You can call errorWindow.blur(); window.focus(); after, forcing the browser to return focus to the previous window.

The effect you're trying to achieve is commonly called a pop-under window.