Upgrade to latest space pen, as an NPM

src/app/editor.coffee

@@ -659,7 +659,7 @@ class Editor extends View
     super
     rootView?.focus()
 
-  afterRemove: ->
+  beforeRemove: ->
     @removed = true
     @activeEditSession?.destroy()
     $(window).off(".editor-#{@id}")

src/app/pane.coffee

@@ -324,5 +324,5 @@ class Pane extends View
     container.adjustPaneDimensions()
     container.trigger 'pane:removed', [this]
 
-  afterRemove: ->
+  beforeRemove: ->
     item.destroy?() for item in @getItems()