diff --git a/src/Pyramid-Toplo/PyramidThemeFromSpaceExtension.class.st b/src/Pyramid-Toplo/PyramidThemeFromSpaceExtension.class.st
index 0be9f984..08429543 100644
--- a/src/Pyramid-Toplo/PyramidThemeFromSpaceExtension.class.st
+++ b/src/Pyramid-Toplo/PyramidThemeFromSpaceExtension.class.st
@@ -11,28 +11,30 @@ Class {
 	#category : #'Pyramid-Toplo-plugin-theme-management'
 }
 
-{ #category : #asserting }
-PyramidThemeFromSpaceExtension class >> shouldInstall [
-
-	^ false
-]
-
 { #category : #actions }
 PyramidThemeFromSpaceExtension >> configureBuilder: aPyramidEditorBuilder [
 
-	(aPyramidEditorBuilder findPlugin: PyramidOpenFromSpacePlugin)
-		addExtension: self.
-	(aPyramidEditorBuilder findPlugin: PyramidSpacePlugin) builder
-		addExtension: self.
-	self themeSpaceSelector: (aPyramidEditorBuilder findPlugin: PyramidToploThemePlugin)
-		themePresenter themeSpaceSelector
+	| pyramidOpenFromSpacePlugin pyramidSpacePlugin pyramidToploThemePlugin |
+	[
+		pyramidOpenFromSpacePlugin := aPyramidEditorBuilder findPlugin:
+			                              PyramidOpenFromSpacePlugin.
+		pyramidSpacePlugin := aPyramidEditorBuilder findPlugin:
+			                      PyramidSpacePlugin.
+		pyramidToploThemePlugin := aPyramidEditorBuilder findPlugin:
+			                           PyramidToploThemePlugin ]
+		on: PyramidNoPluginFoundError
+		do: [ ^ self ].
+
+	pyramidOpenFromSpacePlugin addExtension: self.
+	pyramidSpacePlugin builder addExtension: self.
+	self themeSpaceSelector:
+		pyramidToploThemePlugin themePresenter themeSpaceSelector
 ]
 
 { #category : #'as yet unclassified' }
 PyramidThemeFromSpaceExtension >> configureCloseOnSpace: aSpace [
 
 	aSpace toTheme: themeSpaceSelector currentTheme.
-	aSpace root skinManager postponeRequestSkinIn: aSpace root
 ]
 
 { #category : #'as yet unclassified' }
@@ -40,12 +42,12 @@ PyramidThemeFromSpaceExtension >> configureOpenFromSpace: aSpace [
 	"Do something with the space"
 
 	self defaultToTheme: aSpace toTheme.
-	aSpace root skinManager postponeRequestSkinIn: aSpace root
 ]
 
 { #category : #accessing }
 PyramidThemeFromSpaceExtension >> defaultToTheme [
 
+	defaultToTheme ifNil: [ defaultToTheme := PyramidToploThemePlugin defaultTheme new ].
 	^ defaultToTheme
 ]
 
diff --git a/src/Pyramid-Toplo/PyramidThemeSelectorPresenter.class.st b/src/Pyramid-Toplo/PyramidThemeSelectorPresenter.class.st
index 61c6a357..3f819aee 100644
--- a/src/Pyramid-Toplo/PyramidThemeSelectorPresenter.class.st
+++ b/src/Pyramid-Toplo/PyramidThemeSelectorPresenter.class.st
@@ -24,7 +24,7 @@ PyramidThemeSelectorPresenter >> buttonRefreshTheme [
 { #category : #'as yet unclassified' }
 PyramidThemeSelectorPresenter >> currentTheme [
 
-	^ self themeSelector selectedItem
+	^ self themeSelector selectedItem new
 ]
 
 { #category : #layout }
@@ -58,16 +58,14 @@ PyramidThemeSelectorPresenter >> initializeAllPossibleThemes [
 
 	allThemes := ToTheme allSubclasses select: [ :theme |
 		             theme canBeDefault ].
-	
-	allThemes := allThemes collect: [ :each | each new ].
 
 	self triggerThemeChangement: false.
 	self themeSelector items: allThemes.
 
 	(previousTheme isNotNil and: [ allThemes includes: previousTheme ])
 		ifTrue: [ self themeSelector selectItem: previousTheme ]
-		ifFalse: [ self themeSelector selectItem: allThemes first ].
-	self triggerThemeChangement: true.
+		ifFalse: [ self themeSelector selectItem: PyramidToploThemePlugin defaultTheme ].
+	self triggerThemeChangement: true
 ]
 
 { #category : #initialization }
@@ -96,9 +94,8 @@ PyramidThemeSelectorPresenter >> labelPresenter [
 PyramidThemeSelectorPresenter >> selectTheme: aToTheme [
 
 	self triggerThemeChangement: false.
-	self themeSelector items do: [:theme | (theme class) = (aToTheme class) ifTrue: [ self themeSelector selectItem: (theme) ]].
-	self triggerThemeChangement: true.
-	
+	self themeSelector selectItem: aToTheme class.
+	self triggerThemeChangement: true
 ]
 
 { #category : #'as yet unclassified' }
diff --git a/src/Pyramid-Toplo/PyramidToploThemePlugin.class.st b/src/Pyramid-Toplo/PyramidToploThemePlugin.class.st
index a36f36d5..b1164fa2 100644
--- a/src/Pyramid-Toplo/PyramidToploThemePlugin.class.st
+++ b/src/Pyramid-Toplo/PyramidToploThemePlugin.class.st
@@ -7,9 +7,40 @@ Class {
 		'themePresenter',
 		'themePropertyManager'
 	],
+	#classInstVars : [
+		'defaultTheme'
+	],
 	#category : #'Pyramid-Toplo-plugin-theme-management'
 }
 
+{ #category : #'as yet unclassified' }
+PyramidToploThemePlugin class >> defaultTheme [
+
+	defaultTheme ifNil: [
+		defaultTheme := (ToTheme withAllSubclasses select: [ :e | e canBeDefault ]) last ].
+	^ defaultTheme
+]
+
+{ #category : #'as yet unclassified' }
+PyramidToploThemePlugin class >> defaultTheme: anObject [
+
+	defaultTheme := anObject
+]
+
+{ #category : #'as yet unclassified' }
+PyramidToploThemePlugin class >> defaultThemeSettingOn: aBuilder [
+
+	<systemsettings>
+	(aBuilder pickOne: #defaultTheme)
+		parent: #pyramid;
+		label: 'Choose the default theme.';
+		target: self;
+		domainValues:
+			(ToTheme withAllSubclasses select: #canBeDefault);
+		description:
+			'Define the theme that will be used by default when a new editor is opened.'
+]
+
 { #category : #adding }
 PyramidToploThemePlugin class >> toploAntIconCategory [