Change the setting to open the New Item, Edit Item and View item in a Popup:
SharePoint 2013 by default open the View Item and Edit Item in the full page not as popup view as it in SharePoint 2010.
We can enable this option for a List/Document Library by using the below settings.
· Open the List and Click List à List Settings.
· In the List Settings page, click Advanced settings
· Under Dialogs, select Yes, for Launch forms in a dialog? option.