🐛 Fix #4300 by preventing 'will-navigate'

src/browser/atom-window.coffee

@@ -142,6 +142,8 @@ class AtomWindow
         when 0 then @browserWindow.destroy()
         when 1 then @browserWindow.restart()
 
+    @browserWindow.webContents.on 'will-navigate', (event) -> event.preventDefault()
+
     @setupContextMenu()
 
     if @isSpec