       return
     }
 
+    let prevFirstResponder = self.window.firstResponder
+
     self.window.titlebarAppearsTransparent = true
 
     self.workspace.removeFromSuperview()

    self.workspace.autoPinEdge(toSuperviewEdge: .left)

    self.titlebarThemed = true
  }

  fileprivate func unthemeTitlebar(dueFullScreen: Bool) {

      return
    }

    let prevFirstResponder = self.window.firstResponder
    let prevFrame = self.window.frame

    self.clearCustomTitle()
