All ace editors must die. I found that certain editor modes will leave a mess in memory, so when editors are destroyed, I also set their modes to '' which seems to take care of most of the issue. They still leave memory behind just a little bit, though.

app/views/account/AccountSettingsView.coffee

@@ -234,3 +234,7 @@ module.exports = class AccountSettingsView extends RootView
       $(@).data 'saved-value', $(@).val()
     $('#settings-panes input:checkbox').each ->
       $(@).data 'saved-value', JSON.stringify $(@)[0].checked
+
+  destroy: ->
+    @pictureTreema?.destroy()
+    super()

app/views/common/LevelSessionCodeView.coffee

@@ -26,13 +26,16 @@ module.exports = class LevelSessionCodeView extends CocoView
     
   afterRender: ->
     super()
+    editors = []
     @$el.find('.code').each (index, codeEl) ->
       height = parseInt($(codeEl).data('height'))
       $(codeEl).height(height)
       editor = ace.edit codeEl
       editor.setReadOnly true
+      editors.push editor
       aceSession = editor.getSession()
       aceSession.setMode 'ace/mode/javascript'
+    @editors = editors
     
   organizeCode: ->
     team = @session.get('team') or 'humans'
@@ -47,4 +50,8 @@ module.exports = class LevelSessionCodeView extends CocoView
         name: spell
         height: height
       }
-    filteredSpells 
+    filteredSpells 
+    
+  destroy: ->
+    for editor in @editors
+      @editors

app/views/editor/component/ThangComponentConfigView.coffee

@@ -92,6 +92,10 @@ module.exports = class ThangComponentConfigView extends CocoView
     @trigger 'changed', { component: @component, config: @config }
 
   data: -> @editThangTreema.data
+    
+  destroy: ->
+    @editThangTreema?.destroy()
+    super()
 
 class ComponentConfigNode extends TreemaObjectNode
   nodeDescription: 'Component Property'

app/views/editor/component/ThangComponentsEditView.coffee

@@ -342,7 +342,10 @@ module.exports = class ThangComponentsEditView extends CocoView
       @loadComponents(sparseComponents)
       @components = @components.concat(sparseComponents)
       @onComponentsChanged()
-
+      
+  destroy: ->
+    @componentsTreema?.destroy()
+    super()
 
 class ThangComponentsObjectNode extends TreemaObjectNode
   addNewChild: -> @addNewChildForKey('') # HACK to get the object adding to act more like adding to an array

app/views/editor/level/components/ComponentsTabView.coffee

@@ -81,6 +81,10 @@ module.exports = class ComponentsTabView extends CocoView
   onLevelComponentEditingEnded: (e) ->
     @removeSubView @levelComponentEditView
     @levelComponentEditView = null
+    
+  destroy: ->
+    @componentsTreema?.destroy()
+    super()
 
 class LevelComponentNode extends TreemaObjectNode
   valueClass: 'treema-level-component'

app/views/editor/level/components/LevelComponentEditView.coffee

@@ -84,7 +84,7 @@ module.exports = class LevelComponentEditView extends CocoView
     @levelComponent.set 'configSchema', @configSchemaTreema.data
 
   buildCodeEditor: ->
-    @editor?.destroy()
+    @destroyAceEditor(@editor)
     editorEl = $('<div></div>').text(@levelComponent.get('code')).addClass('inner-editor')
     @$el.find('#component-code-editor').empty().append(editorEl)
     @editor = ace.edit(editorEl[0])
@@ -120,5 +120,7 @@ module.exports = class LevelComponentEditView extends CocoView
     button.find('> span').toggleClass('secret')
 
   destroy: ->
-    @editor?.destroy()
+    @destroyAceEditor(@editor)
+    @componentSettingsTreema?.destroy()
+    @configSchemaTreema?.destroy()
     super()

app/views/editor/level/scripts/ScriptsTabView.coffee

@@ -83,6 +83,7 @@ module.exports = class ScriptsTabView extends CocoView
 
     newPath = selected.getPath()
     return if newPath is @selectedScriptPath
+    @scriptTreema?.destroy()
     @scriptTreema = @$el.find('#script-treema').treema treemaOptions
     @scriptTreema.build()
     @scriptTreema.childrenTreemas?.noteChain?.open()
@@ -114,7 +115,11 @@ module.exports = class ScriptsTabView extends CocoView
   onThangsEdited: (e) ->
     # Update in-place so existing Treema nodes refer to the same array.
     @thangIDs?.splice(0, @thangIDs.length, @getThangIDs()...)
-
+    
+  destroy: ->
+    @scriptTreema?.destroy()
+    @scriptTreemas?.destroy()
+    super()
 
 class ScriptsNode extends TreemaArrayNode
   nodeDescription: 'Script'

app/views/editor/level/settings/SettingsTabView.coffee

@@ -60,6 +60,10 @@ module.exports = class SettingsTabView extends CocoView
   onThangsEdited: (e) ->
     # Update in-place so existing Treema nodes refer to the same array.
     @thangIDs?.splice(0, @thangIDs.length, @getThangIDs()...)
+    
+  destroy: ->
+    @settingsTreema?.destroy()
+    super()
 
 
 class SettingsNode extends TreemaObjectNode

app/views/editor/level/systems/LevelSystemEditView.coffee

@@ -78,7 +78,7 @@ module.exports = class LevelSystemEditView extends CocoView
     @levelSystem.set 'configSchema', @configSchemaTreema.data
 
   buildCodeEditor: ->
-    @editor?.destroy()
+    @destroyAceEditor(@editor)
     editorEl = $('<div></div>').text(@levelSystem.get('code')).addClass('inner-editor')
     @$el.find('#system-code-editor').empty().append(editorEl)
     @editor = ace.edit(editorEl[0])
@@ -114,5 +114,7 @@ module.exports = class LevelSystemEditView extends CocoView
     button.find('> span').toggleClass('secret')
 
   destroy: ->
-    @editor?.destroy()
+    @destroyAceEditor(@editor)
+    @systemSettingsTreema?.destroy()
+    @configSchemaTreema?.destroy()
     super()

app/views/editor/level/systems/SystemsTabView.coffee

@@ -121,6 +121,10 @@ module.exports = class SystemsTabView extends CocoView
       {original: '528114e60268d018e300001a', majorVersion: 0}  # UI
       {original: '528114040268d018e3000011', majorVersion: 0}  # Physics
     ]
+    
+  destroy: ->
+    @systemsTreema?.destroy()
+    super()
 
 class LevelSystemNode extends TreemaObjectNode
   valueClass: 'treema-level-system'

app/views/editor/level/thangs/ThangsTabView.coffee

@@ -183,6 +183,7 @@ module.exports = class ThangsTabView extends CocoView
     @selectAddThangType null
     @surface.destroy()
     $(document).unbind 'contextmenu', @preventDefaultContextMenu
+    @thangsTreema?.destroy()
     super()
 
   onViewSwitched: (e) ->

app/views/editor/thang/ThangTypeColorsTabView.coffee

@@ -21,6 +21,7 @@ module.exports = class ThangTypeColorsTabView extends CocoView
     @interval = setInterval f, 1000
 
   destroy: ->
+    @colorGroups?.destroy()
     clearInterval @interval
     super()
 

app/views/kinds/CocoView.coffee

@@ -65,6 +65,13 @@ module.exports = class CocoView extends Backbone.View
     @destroy = doNothing
     $.noty.closeAll()
 
+  destroyAceEditor: (editor) ->
+    # convenience method to make sure the ace editor is as destroyed as can be 
+    return unless editor
+    session = editor.getSession()
+    session.setMode ''
+    editor.destroy()
+
   afterInsert: ->
 
   willDisappear: ->

app/views/modal/ModelModal.coffee

@@ -69,3 +69,7 @@ module.exports = class ModelModal extends ModalView
     res.success (model, response, options) =>
       return if @destroyed
       @hide()
+
+  destroy: ->
+    @modelTreemas[model].destroy() for model of @modelTreemas
+    super()

app/views/play/level/tome/SpellView.coffee

@@ -80,6 +80,7 @@ module.exports = class SpellView extends CocoView
   createACE: ->
     # Test themes and settings here: http://ace.ajax.org/build/kitchen-sink.html
     aceConfig = me.get('aceConfig') ? {}
+    @destroyAceEditor(@ace)
     @ace = ace.edit @$el.find('.ace')[0]
     @aceSession = @ace.getSession()
     @aceDoc = @aceSession.getDocument()
@@ -710,5 +711,6 @@ module.exports = class SpellView extends CocoView
     @ace?.destroy()
     @aceDoc?.off 'change', @onCodeChangeMetaHandler
     @aceSession?.selection.off 'changeCursor', @onCursorActivity
+    @destroyAceEditor(@ace)
     @debugView?.destroy()
     super()

app/views/user/JobProfileView.coffee

@@ -586,3 +586,7 @@ module.exports = class JobProfileView extends UserView
     session = _.find @sessions.models, (session) -> session.id is sessionID
     modal = new JobProfileCodeModal({session:session})
     @openModalView modal
+
+  destroy: ->
+    @remarkTreema?.destroy()
+    super()