To achieve the desired behavior described above, all you need to do is hold down the Shift key on the keyboard and click the app's icon on the taskbar in Desktop 2:



http://winaero.com/blog/wp-content/uploads/2015/02/hold-shift-key-600x242.png



The new instance on the application will be opened on the active Desktop, so you will get two windows of the Firefox browser, one on Desktop 1 and the other on Desktop 2.



http://winaero.com/blog/wp-content/uploads/2015/02/firefox-running-on-two-desktops-600x450.png

 

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