diff --git a/src/Toplo/BlElement.extension.st b/src/Toplo/BlElement.extension.st
index 263ff5abc..4f5cbb85b 100644
--- a/src/Toplo/BlElement.extension.st
+++ b/src/Toplo/BlElement.extension.st
@@ -15,6 +15,14 @@ BlElement >> dispatchLookEvent: anEvent [
 	self childrenDo: [ :child | child dispatchLookEvent: anEvent ]
 ]
 
+{ #category : #'*Toplo' }
+BlElement >> dispatchSkinChangedEvent [
+
+	self dispatchEvent: ToElementSkinChangedEvent new.
+	self childrenDo: [ :child | child dispatchSkinChangedEvent ]
+
+]
+
 { #category : #'*Toplo' }
 BlElement >> holder [
 
@@ -76,5 +84,7 @@ BlElement >> toTheme: aTheme [
 BlElement >> toThemeChanged [
 
 	self dispatchEvent: ToThemeChangedEvent new.
-	self childrenDo: [ :c | c toThemeChanged ]
+	self childrenDo: [ :c | c toThemeChanged ].
+
+
 ]
diff --git a/src/Toplo/TToCheckable.trait.st b/src/Toplo/TToCheckable.trait.st
index 2e3a26f30..766760c84 100644
--- a/src/Toplo/TToCheckable.trait.st
+++ b/src/Toplo/TToCheckable.trait.st
@@ -56,6 +56,13 @@ TToCheckable >> group: aCheckableGroup [
 	group := aCheckableGroup
 ]
 
+{ #category : #initialization }
+TToCheckable >> initialize [
+
+	self class initializeSlots: self.
+	super initialize.
+]
+
 { #category : #'t - checkable initializing' }
 TToCheckable >> initializeCheckable [
 
diff --git a/src/Toplo/TToSkinable.trait.st b/src/Toplo/TToSkinable.trait.st
index 5a4355ff4..1dcb554ac 100644
--- a/src/Toplo/TToSkinable.trait.st
+++ b/src/Toplo/TToSkinable.trait.st
@@ -44,9 +44,9 @@ TToSkinable >> withSkin: aSkin [
 	self withoutSkin.
 	privateSkin := aSkin.
 	Toplo useLookAndFeel ifTrue: [ ^ self ].
-	privateSkin ifNotNil: [ self addEventHandler: privateSkin ].
-
-	
+	privateSkin ifNotNil: [
+		self addEventHandler: privateSkin.
+		self dispatchSkinChangedEvent ]
 ]
 
 { #category : #'t - skin accessing' }
diff --git a/src/Toplo/ToButtonImageSkin.class.st b/src/Toplo/ToButtonImageSkin.class.st
index fa767145d..b825ad2ed 100644
--- a/src/Toplo/ToButtonImageSkin.class.st
+++ b/src/Toplo/ToButtonImageSkin.class.st
@@ -20,11 +20,11 @@ ToButtonImageSkin >> buttonType: aButtonType [
 ]
 
 { #category : #'api - install/uninstall  hook' }
-ToButtonImageSkin >> whenAddedToSpace: anEvent in: anElement [ 
+ToButtonImageSkin >> onSkinInstalledIn: anElement [
 
 	| iconLook |
 	iconLook := self buttonType iconLookIn: anElement.
 	self addLook: iconLook.
-	super whenAddedToSpace: anEvent in: anElement.
+	super onSkinInstalledIn: anElement
 
 ]
diff --git a/src/Toplo/ToButtonLabelSkin.class.st b/src/Toplo/ToButtonLabelSkin.class.st
index 97a997eba..5514e8719 100644
--- a/src/Toplo/ToButtonLabelSkin.class.st
+++ b/src/Toplo/ToButtonLabelSkin.class.st
@@ -19,6 +19,20 @@ ToButtonLabelSkin >> buttonType: aButtonType [
 	buttonType := aButtonType
 ]
 
+{ #category : #'api - install/uninstall  hook' }
+ToButtonLabelSkin >> onSkinInstalledIn: anElement [
+
+	| labelLook attrBuilder |
+
+	attrBuilder := self textAttributesBuilderFromElement: anElement.
+	labelLook := self buttonType labelLookIn: anElement.
+	labelLook attrBuilder: attrBuilder.
+	self addLook: labelLook.
+
+	super onSkinInstalledIn: anElement
+
+]
+
 { #category : #accessing }
 ToButtonLabelSkin >> textAttributesBuilderFromElement: anElement [
 
@@ -32,17 +46,3 @@ ToButtonLabelSkin >> textAttributesBuilderFromElement: anElement [
 
 	^ builder 
 ]
-
-{ #category : #'api - install/uninstall  hook' }
-ToButtonLabelSkin >> whenAddedToSpace: anEvent in: anElement [ 
-
-	| labelLook attrBuilder |
-
-	attrBuilder := self textAttributesBuilderFromElement: anElement.
-	labelLook := self buttonType labelLookIn: anElement.
-	labelLook attrBuilder: attrBuilder.
-	self addLook: labelLook.
-
-	super whenAddedToSpace: anEvent in: anElement.
-
-]
diff --git a/src/Toplo/ToButtonSkin.class.st b/src/Toplo/ToButtonSkin.class.st
index d9a1595ea..c3df217a6 100644
--- a/src/Toplo/ToButtonSkin.class.st
+++ b/src/Toplo/ToButtonSkin.class.st
@@ -52,6 +52,24 @@ ToButtonSkin >> eventsToHandle [
 	^ super eventsToHandle, { ToButtonIconChanged. ToButtonLabelChanged }
 ]
 
+{ #category : #'api - install/uninstall  hook' }
+ToButtonSkin >> onSkinInstalledIn: anElement [
+
+	" must send to super ** after ** the look is initialize from type "
+	self type onSkinInstalled: self in: anElement.
+	super onSkinInstalledIn: anElement
+
+]
+
+{ #category : #'api - install/uninstall  hook' }
+ToButtonSkin >> onSkinUninstalledIn: anElement [
+
+	self type onSkinUninstalled: self in: anElement.
+	super onSkinUninstalledIn: anElement
+
+
+]
+
 { #category : #accessing }
 ToButtonSkin >> type [
 
@@ -66,20 +84,3 @@ ToButtonSkin >> type: aSkinType [
 	"#default, #primary, #link or #text"
 	type := aSkinType
 ]
-
-{ #category : #'api - install/uninstall  hook' }
-ToButtonSkin >> whenAddedToSpace: anEvent in: anElement [
-
-	" must send to super ** after ** the look is initialize from type "
-	self type whenAddedToSpace: anEvent in: anElement fromSkin: self.
-	super whenAddedToSpace: anEvent in: anElement.
-
-]
-
-{ #category : #'api - install/uninstall  hook' }
-ToButtonSkin >> whenRemovedFromSpace: anEvent in: anElement [
-
-	self type whenRemovedFromSpace: anEvent in: anElement fromSkin: self.
-	super whenRemovedFromSpace: anEvent in: anElement.
-
-]
diff --git a/src/Toplo/ToButtonType.class.st b/src/Toplo/ToButtonType.class.st
index 5f1d91400..c6a8200f5 100644
--- a/src/Toplo/ToButtonType.class.st
+++ b/src/Toplo/ToButtonType.class.st
@@ -78,19 +78,7 @@ ToButtonType >> labelLookIn: anElement [
 ]
 
 { #category : #'api - install/uninstall  hook' }
-ToButtonType >> regularFormLookIn: anElement [
-
-	self subclassResponsibility 
-]
-
-{ #category : #'api - install/uninstall  hook' }
-ToButtonType >> regularLabelLookIn: anElement [
-
-	self subclassResponsibility 
-]
-
-{ #category : #'api - install/uninstall  hook' }
-ToButtonType >> whenAddedToSpace: anEvent in: anElement fromSkin: aSkin [
+ToButtonType >> onSkinInstalled: aSkin in: anElement [
 
 	| borderLook backgroundLook |
 	anElement geometry: (BlRoundedRectangleGeometry cornerRadius: anElement toTheme borderRadius).
@@ -108,7 +96,19 @@ ToButtonType >> whenAddedToSpace: anEvent in: anElement fromSkin: aSkin [
 ]
 
 { #category : #'api - install/uninstall  hook' }
-ToButtonType >> whenRemovedFromSpace: anEvent in: anElement fromSkin: aSkin [
+ToButtonType >> onSkinUninstalled: aSkin in: anElement [
 
 
 ]
+
+{ #category : #'api - install/uninstall  hook' }
+ToButtonType >> regularFormLookIn: anElement [
+
+	self subclassResponsibility 
+]
+
+{ #category : #'api - install/uninstall  hook' }
+ToButtonType >> regularLabelLookIn: anElement [
+
+	self subclassResponsibility 
+]
diff --git a/src/Toplo/ToCheckableSkin.class.st b/src/Toplo/ToCheckableSkin.class.st
index 750966781..2d975d989 100644
--- a/src/Toplo/ToCheckableSkin.class.st
+++ b/src/Toplo/ToCheckableSkin.class.st
@@ -22,18 +22,10 @@ ToCheckableSkin >> indeterminateImageIn: anElement [
 	^ self subclassResponsibility 
 ]
 
-{ #category : #accessing }
-ToCheckableSkin >> uncheckedImageIn: anElement [
-
-	^ self subclassResponsibility 
-]
-
 { #category : #'api - install/uninstall  hook' }
-ToCheckableSkin >> whenAddedToSpace: anEvent in: anElement [
+ToCheckableSkin >> onSkinInstalledIn: anElement [
 
-	super whenAddedToSpace: anEvent in: anElement.
-	anElement spacingWidth:
-		anElement toTheme paddingContentHorizontal / 2.
+	anElement spacingWidth: anElement toTheme paddingContentHorizontal / 2.
 	anElement icon: (ToImage inner: (anElement isChecked
 				  ifTrue: [ self checkedImageIn: anElement ]
 				  ifFalse: [ self uncheckedImageIn: anElement ])).
@@ -42,5 +34,12 @@ ToCheckableSkin >> whenAddedToSpace: anEvent in: anElement [
 			 checkedImage: (self checkedImageIn: anElement);
 			 uncheckedImage: (self uncheckedImageIn: anElement);
 			 indeterminateImage: (self indeterminateImageIn: anElement);
-			 yourself)
+			 yourself).
+	super onSkinInstalledIn: anElement
+]
+
+{ #category : #accessing }
+ToCheckableSkin >> uncheckedImageIn: anElement [
+
+	^ self subclassResponsibility 
 ]
diff --git a/src/Toplo/ToCheckboxImageSkin.class.st b/src/Toplo/ToCheckboxImageSkin.class.st
index 45054e317..8c2c74d9a 100644
--- a/src/Toplo/ToCheckboxImageSkin.class.st
+++ b/src/Toplo/ToCheckboxImageSkin.class.st
@@ -5,7 +5,7 @@ Class {
 }
 
 { #category : #'api - install/uninstall  hook' }
-ToCheckboxImageSkin >> whenAddedToSpace: anEvent in: anElement [ 
+ToCheckboxImageSkin >> onSkinInstalledIn: anElement [
 
 	| borderLook |
 		
@@ -17,6 +17,6 @@ ToCheckboxImageSkin >> whenAddedToSpace: anEvent in: anElement [
 				width: 1.
 	self addLook: borderLook.
 
-	super whenAddedToSpace: anEvent in: anElement.
+	super onSkinInstalledIn: anElement
 
 ]
diff --git a/src/Toplo/ToElementSkinChangedEvent.class.st b/src/Toplo/ToElementSkinChangedEvent.class.st
new file mode 100644
index 000000000..ee66a554f
--- /dev/null
+++ b/src/Toplo/ToElementSkinChangedEvent.class.st
@@ -0,0 +1,11 @@
+Class {
+	#name : #ToElementSkinChangedEvent,
+	#superclass : #BlEvent,
+	#category : #'Toplo-Core-Theme'
+}
+
+{ #category : #sending }
+ToElementSkinChangedEvent >> sendTo: anObject [
+
+	anObject elementSkinChangedEvent: self
+]
diff --git a/src/Toplo/ToImage.class.st b/src/Toplo/ToImage.class.st
index 9f9b977c7..93b872b94 100644
--- a/src/Toplo/ToImage.class.st
+++ b/src/Toplo/ToImage.class.st
@@ -41,11 +41,13 @@ ToImage >> hasInnerImage [
 ToImage >> initialize [
 
 	super initialize.
-	
+
 	self fitContent.
 	self innerImage: self defaultInnerImage.
 	" I ** must be ** considered as a leaf of a UI element tree. Otherwise, click may not work on me. This is why my children are not allowed to manage mouse events. Related to https://github.com/plantec/Toplo/issues/41"
 	self preventChildrenMouseEvents.
+	self whenInnerImageChangedDo: [ :new :prev |
+		self dispatchEvent: (ToInnerImageChangedEvent current: new previous: prev) ]
 ]
 
 { #category : #'form accessing' }
@@ -75,7 +77,7 @@ ToImage >> innerImage: anImage [
 ]
 
 { #category : #'api - change hook' }
-ToImage >> whenInnerImageReplacedDo: aBlock [
+ToImage >> whenInnerImageChangedDo: aBlock [
 
 	"set a block to perform after that the image has been changed, and its action performed"
 
diff --git a/src/Toplo/ToImageModel.class.st b/src/Toplo/ToImageModel.class.st
index 7e25d069b..f3503eda0 100644
--- a/src/Toplo/ToImageModel.class.st
+++ b/src/Toplo/ToImageModel.class.st
@@ -17,9 +17,9 @@ ToImageModel >> privateWidgetClass [
 ]
 
 { #category : #'api - change hook' }
-ToImageModel >> whenInnerImageReplacedDo: aBlock [
+ToImageModel >> whenInnerImageChangedDo: aBlock [
 
 	"set a block to perform after that the image has been changed, and its action performed"
 
-	self widgetDo: [ :widget | widget whenInnerImageReplacedDo: aBlock ]
+	self widgetDo: [ :widget | widget whenInnerImageChangedDo: aBlock ]
 ]
diff --git a/src/Toplo/ToInnerImageChangedEvent.class.st b/src/Toplo/ToInnerImageChangedEvent.class.st
new file mode 100644
index 000000000..266831b3a
--- /dev/null
+++ b/src/Toplo/ToInnerImageChangedEvent.class.st
@@ -0,0 +1,11 @@
+Class {
+	#name : #ToInnerImageChangedEvent,
+	#superclass : #ToElementPropertyChanged,
+	#category : #'Toplo-Widget-Image'
+}
+
+{ #category : #sending }
+ToInnerImageChangedEvent >> sendTo: anObject [
+
+	anObject innerImageChanged: self
+]
diff --git a/src/Toplo/ToLabelMultiLineInnerElement.class.st b/src/Toplo/ToLabelMultiLineInnerElement.class.st
index d5aa0d72f..314b10845 100644
--- a/src/Toplo/ToLabelMultiLineInnerElement.class.st
+++ b/src/Toplo/ToLabelMultiLineInnerElement.class.st
@@ -1,6 +1,6 @@
 Class {
 	#name : #ToLabelMultiLineInnerElement,
-	#superclass : #BlElement,
+	#superclass : #ToElement,
 	#traits : 'TToLabelInnerElement + TObservable + TBlLayoutResizable',
 	#classTraits : 'TToLabelInnerElement classTrait + TObservable classTrait + TBlLayoutResizable classTrait',
 	#instVars : [
diff --git a/src/Toplo/ToRadioImageSkin.class.st b/src/Toplo/ToRadioImageSkin.class.st
index 82b7b04da..75ffd13ca 100644
--- a/src/Toplo/ToRadioImageSkin.class.st
+++ b/src/Toplo/ToRadioImageSkin.class.st
@@ -5,7 +5,7 @@ Class {
 }
 
 { #category : #'api - install/uninstall  hook' }
-ToRadioImageSkin >> whenAddedToSpace: anEvent in: anElement [ 
+ToRadioImageSkin >> onSkinInstalledIn: anElement [
 
 	| borderLook |
 		
@@ -17,6 +17,6 @@ ToRadioImageSkin >> whenAddedToSpace: anEvent in: anElement [
 				width: 1.
 	self addLook: borderLook.
 
-	super whenAddedToSpace: anEvent in: anElement.
+	super onSkinInstalledIn: anElement
 
 ]
diff --git a/src/Toplo/ToSandBox.class.st b/src/Toplo/ToSandBox.class.st
index f0abe71e4..827cc4198 100644
--- a/src/Toplo/ToSandBox.class.st
+++ b/src/Toplo/ToSandBox.class.st
@@ -943,14 +943,14 @@ ToSandBox class >> example_ToButtonSkins [
 	
 	space root layout: (BlLinearLayout vertical cellSpacing: 10).
 
-	"themeSwitcher := ToChoiceBox new.
+	themeSwitcher := ToChoiceBox new.
 	themeSwitcher data addAll: { ToThemeLight. ToThemeDark }.
 			
 	themeSwitcher whenSelectedIndexChangedDo: [ space toTheme: themeSwitcher selectedData new ].
 	themeSwitcher selectData: space toTheme class.
-	space root addChild: themeSwitcher."
+	space root addChild: themeSwitcher.
 
-space switchThemeDarkOrLight.
+"space switchThemeDarkOrLight."
 
 	butBuilder := [ ToImage new innerImage: ToThemeIcons iconSearchOutlined16x16 ].
 	buttonSpecsBuilder := [ {
@@ -1115,8 +1115,9 @@ ToSandBox class >> example_ToButtonWithPrimarySkin [
 	space root addChild: button1.	
 	space root when: BlElementAddedToSceneGraphEvent do: [  
 		button1 labelText: 'Primary button 3'.
-		button1 iconImage: (ToThemeIcons iconSearchOutlined16x16) ].
+		button1 icon: (ToImage inner: (ToThemeIcons iconSearchOutlined16x16)) ].
 	space show.
+	
 ]
 
 { #category : #button }
diff --git a/src/Toplo/ToToggleSkin.class.st b/src/Toplo/ToToggleSkin.class.st
index e2d5b9028..1c07b2cdc 100644
--- a/src/Toplo/ToToggleSkin.class.st
+++ b/src/Toplo/ToToggleSkin.class.st
@@ -32,6 +32,20 @@ ToToggleSkin >> buttonLabelChanged: anEvent [
 
 ]
 
+{ #category : #'api - install/uninstall  hook' }
+ToToggleSkin >> onSkinInstalledIn: anElement [
+
+	anElement spacingWidth: anElement toTheme paddingContentHorizontal / 2.
+	anElement geometry: (BlRoundedRectangleGeometry cornerRadius: (self trackBorderRadiusIn: anElement)).
+	anElement padding: (BlInsets
+			 top: anElement toTheme paddingXS / 2
+			 left: anElement toTheme paddingContentHorizontal
+			 bottom: anElement toTheme paddingXS / 2
+			 right: anElement toTheme paddingContentHorizontal).
+	self setupTrackElementIn: anElement.
+	super onSkinInstalledIn: anElement
+]
+
 { #category : #'api - install/uninstall  hook' }
 ToToggleSkin >> setupTrackElementIn: anElement [
 
@@ -58,17 +72,3 @@ ToToggleSkin >> trackBorderRadiusIn: anElement [
 
 	^ 26
 ]
-
-{ #category : #'api - install/uninstall  hook' }
-ToToggleSkin >> whenAddedToSpace: anEvent in: anElement [
-
-	anElement spacingWidth: anElement toTheme paddingContentHorizontal / 2.
-	anElement geometry: (BlRoundedRectangleGeometry cornerRadius: (self trackBorderRadiusIn: anElement)).
-	anElement padding: (BlInsets
-			 top: anElement toTheme paddingXS / 2
-			 left: anElement toTheme paddingContentHorizontal
-			 bottom: anElement toTheme paddingXS / 2
-			 right: anElement toTheme paddingContentHorizontal).
-	self setupTrackElementIn: anElement.
-	super whenAddedToSpace: anEvent in: anElement
-]
diff --git a/src/Toplo/ToToggleTrackSkin.class.st b/src/Toplo/ToToggleTrackSkin.class.st
index 32c9d862f..1949a90b4 100644
--- a/src/Toplo/ToToggleTrackSkin.class.st
+++ b/src/Toplo/ToToggleTrackSkin.class.st
@@ -7,14 +7,8 @@ Class {
 	#category : #'Toplo-Widget-Button-Toggle-Skins'
 }
 
-{ #category : #accessing }
-ToToggleTrackSkin >> toggleButton: aToggleButton [
-
-	toggleButton := aToggleButton
-]
-
 { #category : #'api - install/uninstall  hook' }
-ToToggleTrackSkin >> whenAddedToSpace: anEvent in: anElement [
+ToToggleTrackSkin >> onSkinInstalledIn: anElement [
 
 	toggleButton := anElement parent.
 	self addLook: (ToBackgroundLook new
@@ -35,5 +29,11 @@ ToToggleTrackSkin >> whenAddedToSpace: anEvent in: anElement [
 			 animate: true;
 			 toggleButton: toggleButton;
 			 yourself).
-	super whenAddedToSpace: anEvent in: anElement
+	super onSkinInstalledIn: anElement
+]
+
+{ #category : #accessing }
+ToToggleTrackSkin >> toggleButton: aToggleButton [
+
+	toggleButton := aToggleButton
 ]
diff --git a/src/Toplo/ToWidgetSkin.class.st b/src/Toplo/ToWidgetSkin.class.st
index a42c2ea9f..8004a4a2f 100644
--- a/src/Toplo/ToWidgetSkin.class.st
+++ b/src/Toplo/ToWidgetSkin.class.st
@@ -2,7 +2,6 @@ Class {
 	#name : #ToWidgetSkin,
 	#superclass : #BlCustomEventHandler,
 	#instVars : [
-		'addedToSpace',
 		'look'
 	],
 	#category : #'Toplo-Core-Theme'
@@ -16,18 +15,10 @@ ToWidgetSkin >> addLook: aLook [
 	self privateLook: aLook
 ]
 
-{ #category : #accessing }
-ToWidgetSkin >> addedToSpace [
-
-	^ addedToSpace 
-]
-
-{ #category : #'event handling' }
+{ #category : #'as yet unclassified' }
 ToWidgetSkin >> elementAddedToSceneGraphEvent: anEvent [
 
-	addedToSpace ifTrue: [ ^ self ].
-	self whenAddedToSpace: anEvent in: anEvent currentTarget.
-	addedToSpace := true
+	self whenAddedToSpace: anEvent in: anEvent currentTarget
 ]
 
 { #category : #'event handling' }
@@ -36,25 +27,22 @@ ToWidgetSkin >> elementLookEvent: anEvent [
 	anEvent sendTo: self look
 ]
 
-{ #category : #'event handling' }
+{ #category : #'as yet unclassified' }
 ToWidgetSkin >> elementRemovedFromSceneGraphEvent: anEvent [
 
-	addedToSpace ifFalse: [ ^ self ].
-	self whenRemovedFromSpace:  anEvent in: anEvent currentTarget.
-	addedToSpace := false
+	self whenRemovedFromSpace: anEvent in: anEvent currentTarget
 ]
 
-{ #category : #'api - accessing' }
-ToWidgetSkin >> eventsToHandle [
+{ #category : #'event handling' }
+ToWidgetSkin >> elementSkinChangedEvent: anEvent [
 
-	^ { BlElementAddedToSceneGraphEvent. BlElementRemovedFromSceneGraphEvent. ToElementLookEvent }
+	
 ]
 
-{ #category : #initialization }
-ToWidgetSkin >> initialize [ 
+{ #category : #'api - accessing' }
+ToWidgetSkin >> eventsToHandle [
 
-	super initialize.
-	addedToSpace := false.
+	^ { BlElementAddedToSceneGraphEvent. BlElementRemovedFromSceneGraphEvent . ToElementLookEvent }
 ]
 
 { #category : #accessing }
@@ -68,10 +56,20 @@ ToWidgetSkin >> onInstalledIn: anElement [
 
 	super onInstalledIn: anElement.
 	self privateLook: ToNullElementLook new.
-	addedToSpace := anElement isAttachedToSceneGraph.
-	addedToSpace
-		ifTrue: [ self whenAddedToSpace: nil in: anElement ]
-		ifFalse: [ self whenRemovedFromSpace: nil in: anElement ]
+	
+	
+]
+
+{ #category : #'api - install/uninstall  hook' }
+ToWidgetSkin >> onSkinInstalledIn: anElement [
+
+
+]
+
+{ #category : #'api - install/uninstall  hook' }
+ToWidgetSkin >> onSkinUninstalledIn: anElement [
+
+
 ]
 
 { #category : #'api - install/uninstall  hook' }
@@ -98,20 +96,24 @@ ToWidgetSkin >> removeLook: aLook [
 { #category : #'event handling' }
 ToWidgetSkin >> themeChangedEvent: anEvent [
 
-	self whenRemovedFromSpace: anEvent in: anEvent currentTarget.
-	self whenAddedToSpace: anEvent in: anEvent currentTarget
+	self onSkinUninstalledIn: anEvent currentTarget.
+	self onSkinInstalledIn: anEvent currentTarget.
+	anEvent currentTarget dispatchLookEvent: ToInstallLookEvent new.
+	anEvent currentTarget whenLayoutedDoOnce: [ anEvent currentTarget switchToState: ToInitialState new ]
 ]
 
 { #category : #'api - install/uninstall  hook' }
 ToWidgetSkin >> whenAddedToSpace: anEvent in: anElement [
 
-	anElement whenLayoutedDoOnce: [
-		anElement dispatchLookEvent: (ToInstallLookEvent new copyFrom: anEvent).
-		anElement dispatchLookEvent:	((ToElementStateChangedEvent new state: ToInitialState new) copyFrom: anEvent) ]
+	self onSkinInstalledIn: anElement.
+	anElement dispatchLookEvent: ToInstallLookEvent new.
+	anElement whenLayoutedDoOnce: [ anElement switchToState: ToInitialState new ]
 ]
 
 { #category : #'api - install/uninstall  hook' }
 ToWidgetSkin >> whenRemovedFromSpace: anEvent in: anElement [
 
-	anElement dispatchLookEvent: (ToUninstallLookEvent new copyFrom: anEvent)
+	anElement dispatchLookEvent: ToUninstallLookEvent new.
+	self onSkinUninstalledIn: anElement.
+
 ]
diff --git a/src/Toplo/ToWindowElement.class.st b/src/Toplo/ToWindowElement.class.st
index 0e02b41f4..da2162a1c 100644
--- a/src/Toplo/ToWindowElement.class.st
+++ b/src/Toplo/ToWindowElement.class.st
@@ -85,6 +85,7 @@ ToWindowElement >> initialize [
 		geometry: self defaultGeometry;
 		clipChildren: false;
 		fitContent.
+	self constraintsDo: [ :c | c ignoreByLayout ].
 		
 	self addChildren: self elements.
 ]