diff --git a/AdvancedDockingSystem/AdvancedDockingSystem.pro b/AdvancedDockingSystem/AdvancedDockingSystem.pro
index e84b2fa..f89c77b 100644
--- a/AdvancedDockingSystem/AdvancedDockingSystem.pro
+++ b/AdvancedDockingSystem/AdvancedDockingSystem.pro
@@ -7,6 +7,8 @@ TEMPLATE = lib
 
 CONFIG += staticlib
 
+VERSION = 0.1.0
+
 INCLUDEPATH += $$PWD/src
 INCLUDEPATH += $$PWD/include
 
diff --git a/AdvancedDockingSystem/include/ads/ContainerWidget.h b/AdvancedDockingSystem/include/ads/ContainerWidget.h
index 1017b9d..82118bf 100644
--- a/AdvancedDockingSystem/include/ads/ContainerWidget.h
+++ b/AdvancedDockingSystem/include/ads/ContainerWidget.h
@@ -10,6 +10,7 @@ class QSplitter;
 class QMenu;
 
 #include "ads/API.h"
+#include "ads/Internal.h"
 #include "ads/SectionContent.h"
 #include "ads/SectionWidget.h"
 #include "ads/FloatingWidget.h"
@@ -50,6 +51,18 @@ public:
 	 */
 	SectionWidget* addSectionContent(const SectionContent::RefPtr& sc, SectionWidget* sw = NULL, DropArea area = CenterDropArea);
 
+	/*!
+	 * Shows the specific SectionContent in UI.
+	 * Independed of the current state, whether it is used inside a section or is floating.
+	 */
+	bool showSectionContent(const SectionContent::RefPtr& sc);
+
+	/*!
+	 * Closes the specified SectionContent from UI.
+	 * Independed of the current state, whether it is used inside a section or is floating.
+	 */
+	bool hideSectionContent(const SectionContent::RefPtr& sc);
+
 	/*!
 	 * Creates a QMenu based on available SectionContents.
 	 * The caller is responsible to delete the menu.
@@ -102,16 +115,17 @@ signals:
 	void orientationChanged();
 
 private:
-	// Sections of this container
 	QList<SectionWidget*> _sections;
-
-	//Floatings of this container
 	QList<FloatingWidget*> _floatings;
 
+	QHash<int, HiddenSectionItem> _hiddenSectionContents;
+
+
 	// Layout stuff
 	QGridLayout* _mainLayout;
 	Qt::Orientation _orientation;
-	QPointer<QSplitter> _splitter; // $mfreiholz: I'd like to remove this variable entirely.
+	QPointer<QSplitter> _splitter; // $mfreiholz: I'd like to remove this variable entirely,
+								   // because it changes during user interaction anyway.
 };
 
 ADS_NAMESPACE_END
diff --git a/AdvancedDockingSystem/include/ads/Internal.h b/AdvancedDockingSystem/include/ads/Internal.h
index bf37299..062b833 100644
--- a/AdvancedDockingSystem/include/ads/Internal.h
+++ b/AdvancedDockingSystem/include/ads/Internal.h
@@ -28,5 +28,19 @@ public:
 };
 
 
+class HiddenSectionItem
+{
+public:
+	HiddenSectionItem() :
+		preferredSectionId(-1),
+		preferredSectionIndex(-1)
+	{}
+
+	int preferredSectionId;
+	int preferredSectionIndex;
+	InternalContentData data;
+};
+
+
 ADS_NAMESPACE_END
 #endif
diff --git a/AdvancedDockingSystem/include/ads/SectionContentWidget.h b/AdvancedDockingSystem/include/ads/SectionContentWidget.h
index 1529fd1..fa59b8b 100644
--- a/AdvancedDockingSystem/include/ads/SectionContentWidget.h
+++ b/AdvancedDockingSystem/include/ads/SectionContentWidget.h
@@ -18,6 +18,7 @@ class SectionContentWidget : public QFrame
 
 public:
 	SectionContentWidget(SectionContent::RefPtr c, QWidget* parent = 0);
+	virtual ~SectionContentWidget();
 
 private:
 	SectionContent::RefPtr _content;
diff --git a/AdvancedDockingSystem/include/ads/SectionTitleWidget.h b/AdvancedDockingSystem/include/ads/SectionTitleWidget.h
index a7cd84e..faa7ce5 100644
--- a/AdvancedDockingSystem/include/ads/SectionTitleWidget.h
+++ b/AdvancedDockingSystem/include/ads/SectionTitleWidget.h
@@ -34,6 +34,7 @@ class SectionTitleWidget : public QFrame
 
 public:
 	SectionTitleWidget(SectionContent::RefPtr content, QWidget* parent);
+	virtual ~SectionTitleWidget();
 
 	bool isActiveTab() const;
 	void setActiveTab(bool active);
diff --git a/AdvancedDockingSystem/include/ads/SectionWidget.h b/AdvancedDockingSystem/include/ads/SectionWidget.h
index c248de4..d75e502 100644
--- a/AdvancedDockingSystem/include/ads/SectionWidget.h
+++ b/AdvancedDockingSystem/include/ads/SectionWidget.h
@@ -9,13 +9,13 @@ class QBoxLayout;
 class QStackedLayout;
 
 #include "ads/API.h"
+#include "ads/Internal.h"
 #include "ads/SectionContent.h"
 
 ADS_NAMESPACE_BEGIN
 class ContainerWidget;
 class SectionTitleWidget;
 class SectionContentWidget;
-class InternalContentData;
 
 // SectionWidget manages multiple instances of SectionContent.
 // It displays a title TAB, which is clickable and will switch to
@@ -37,10 +37,10 @@ public:
 	QRect contentAreaGeometry() const;
 
 	const QList<SectionContent::RefPtr>& contents() const { return _contents; }
-	void addContent(SectionContent::RefPtr c);
+	void addContent(const SectionContent::RefPtr& c);
 	void addContent(const InternalContentData& data, bool autoActivate);
 	bool takeContent(int uid, InternalContentData& data);
-	int indexOfContent(SectionContent::RefPtr c) const;
+	int indexOfContent(const SectionContent::RefPtr& c) const;
 	int indexOfContentByTitlePos(const QPoint& pos, QWidget* exclude = NULL) const;
 
 	int currentIndex() const;
@@ -49,11 +49,9 @@ public:
 public slots:
 	void setCurrentIndex(int index);
 
-protected:
-	virtual void paintEvent(QPaintEvent*);
-
 private slots:
 	void onSectionTitleClicked();
+	void onCloseButtonClicked();
 
 private:
 	const int _uid;
diff --git a/AdvancedDockingSystem/src/ContainerWidget.cpp b/AdvancedDockingSystem/src/ContainerWidget.cpp
index 0bb390a..d6ee708 100644
--- a/AdvancedDockingSystem/src/ContainerWidget.cpp
+++ b/AdvancedDockingSystem/src/ContainerWidget.cpp
@@ -73,52 +73,164 @@ SectionWidget* ContainerWidget::addSectionContent(const SectionContent::RefPtr&
 	return dropContent(data, sw, area, false);
 }
 
-QMenu* ContainerWidget::createContextMenu() const
+bool ContainerWidget::showSectionContent(const SectionContent::RefPtr& sc)
 {
-	QMenu* m = new QMenu(NULL);
+	// Search SC in floatings
+	for (int i = 0; i < _floatings.count(); ++i)
+	{
+		const bool found = _floatings.at(i)->content()->uid() == sc->uid();
+		if (!found)
+			continue;
+		_floatings.at(i)->setVisible(true);
+		return true;
+	}
 
-	// Contents of SectionWidgets
-	for (int i = 0; i < _sections.size(); ++i)
+	// Search SC in hidden sections
+	// Try to show them in the last position, otherwise simply append
+	// it to the first section (or create a new section?)
+	if (_hiddenSectionContents.contains(sc->uid()))
+	{
+		const HiddenSectionItem hsi = _hiddenSectionContents.take(sc->uid());
+		hsi.data.titleWidget->setVisible(true);
+		hsi.data.contentWidget->setVisible(true);
+		SectionWidget* sw = NULL;
+		if (hsi.preferredSectionId > 0 && (sw = SectionWidget::LookupMap.value(hsi.preferredSectionId)) != NULL)
+		{
+			sw->addContent(hsi.data, true);
+			return true;
+		}
+		else if (_sections.size() > 0 && (sw = _sections.first()) != NULL)
+		{
+			sw->addContent(hsi.data, true);
+			return true;
+		}
+		else
+		{
+			qDebug() << "TODO Create new SW here and add SC";
+			return true;
+		}
+	}
+	qFatal("Unable to show SectionContent, don't know where 8-/");
+	return false;
+}
+
+bool ContainerWidget::hideSectionContent(const SectionContent::RefPtr& sc)
+{
+	// Search SC in floatings
+	// We can simply hide floatings, nothing else required.
+	for (int i = 0; i < _floatings.count(); ++i)
+	{
+		const bool found = _floatings.at(i)->content()->uid() == sc->uid();
+		if (!found)
+			continue;
+		_floatings.at(i)->setVisible(false);
+		return true;
+	}
+
+	// Search SC in sections
+	// It's required to remove the SC from SW completely and hold it in a
+	// separate list as long as a "showSectionContent" gets called for the SC again.
+	// In case that the SW does not have any other SCs, we need to delete it.
+	for (int i = 0; i < _sections.count(); ++i)
 	{
 		SectionWidget* sw = _sections.at(i);
-		QList<SectionContent::RefPtr> contents = sw->contents();
-		foreach (const SectionContent::RefPtr& c, contents)
+		const bool found = sw->indexOfContent(sc) >= 0;
+		if (!found)
+			continue;
+
+		HiddenSectionItem hsi;
+		hsi.preferredSectionId = sw->uid();
+		hsi.preferredSectionIndex = sw->indexOfContent(sc);
+		if (!sw->takeContent(sc->uid(), hsi.data))
+			return false;
+
+		hsi.data.titleWidget->setVisible(false);
+		hsi.data.contentWidget->setVisible(false);
+		_hiddenSectionContents.insert(sc->uid(), hsi);
+
+		if (sw->contents().isEmpty())
 		{
-			QAction* a = m->addAction(QIcon(), c->uniqueName());
-			a->setProperty("uid", c->uid());
+			delete sw;
+			sw = NULL;
+			deleteEmptySplitter(this);
+		}
+		return true;
+	}
+	qFatal("Unable to hide SectionContent, don't know this one 8-/");
+	return false;
+}
+
+QMenu* ContainerWidget::createContextMenu() const
+{
+	// Fill map with actions (sorted by key!)
+	QMap<QString, QAction*> actions;
+
+	// Visible contents of sections
+	for (int i = 0; i < _sections.size(); ++i)
+	{
+		const SectionWidget* sw = _sections.at(i);
+		const QList<SectionContent::RefPtr>& contents = sw->contents();
+		foreach (const SectionContent::RefPtr& sc, contents)
+		{
+			QAction* a = new QAction(QIcon(), sc->uniqueName(), NULL);
+			a->setObjectName(QString("ads-action-sc-%1").arg(QString::number(sc->uid())));
+			a->setProperty("uid", sc->uid());
 			a->setProperty("type", "section");
 			a->setCheckable(true);
-			a->setChecked(c->titleWidget()->isVisible());
+			a->setChecked(true);
 #if QT_VERSION >= 0x050000
 			QObject::connect(a, &QAction::toggled, this, &ContainerWidget::onActionToggleSectionContentVisibility);
 #else
 			QObject::connect(a, SIGNAL(toggled(bool)), this, SLOT(onActionToggleSectionContentVisibility(bool)));
 #endif
+			actions.insert(a->text(), a);
 		}
 	}
 
-	// Contents of FloatingWidgets
-	if (_floatings.size())
+	// Hidden contents of sections
+	QHashIterator<int, HiddenSectionItem> hiddenIter(_hiddenSectionContents);
+	while (hiddenIter.hasNext())
 	{
-		if (m->actions().size())
-			m->addSeparator();
-		for (int i = 0; i < _floatings.size(); ++i)
-		{
-			FloatingWidget* fw = _floatings.at(i);
-			SectionContent::RefPtr c = fw->content();
-			QAction* a = m->addAction(QIcon(), c->uniqueName());
-			a->setProperty("uid", c->uid());
-			a->setProperty("type", "floating");
-			a->setCheckable(true);
-			a->setChecked(fw->isVisible());
+		hiddenIter.next();
+		const SectionContent::RefPtr sc = hiddenIter.value().data.content;
+
+		QAction* a = new QAction(QIcon(), sc->uniqueName(), NULL);
+		a->setObjectName(QString("ads-action-sc-%1").arg(QString::number(sc->uid())));
+		a->setProperty("uid", sc->uid());
+		a->setProperty("type", "section");
+		a->setCheckable(true);
+		a->setChecked(false);
 #if QT_VERSION >= 0x050000
-			QObject::connect(a, &QAction::toggled, fw, &FloatingWidget::setVisible);
+			QObject::connect(a, &QAction::toggled, this, &ContainerWidget::onActionToggleSectionContentVisibility);
 #else
-			QObject::connect(a, SIGNAL(toggled(bool)), fw, SLOT(setVisible(bool)));
+			QObject::connect(a, SIGNAL(toggled(bool)), this, SLOT(onActionToggleSectionContentVisibility(bool)));
 #endif
-		}
+		actions.insert(a->text(), a);
 	}
 
+	// Floating contents
+	for (int i = 0; i < _floatings.size(); ++i)
+	{
+		const FloatingWidget* fw = _floatings.at(i);
+		const SectionContent::RefPtr sc = fw->content();
+
+		QAction* a = new QAction(QIcon(), sc->uniqueName(), NULL);
+		a->setObjectName(QString("ads-action-sc-%1").arg(QString::number(sc->uid())));
+		a->setProperty("uid", sc->uid());
+		a->setProperty("type", "floating");
+		a->setCheckable(true);
+		a->setChecked(fw->isVisible());
+#if QT_VERSION >= 0x050000
+		QObject::connect(a, &QAction::toggled, fw, &FloatingWidget::setVisible);
+#else
+		QObject::connect(a, SIGNAL(toggled(bool)), fw, SLOT(setVisible(bool)));
+#endif
+		actions.insert(a->text(), a);
+	}
+
+	// Create menu from "actions"
+	QMenu* m = new QMenu(NULL);
+	m->addActions(actions.values());
 	return m;
 }
 
@@ -208,15 +320,21 @@ bool ContainerWidget::restoreState(const QByteArray& data)
 
 		// What should we do with a drunken sailor.. what should.. erm..
 		// .. we do with the left-contents?
-		if (!_sections.isEmpty())
+		// We might need to add them into the hidden-list, if no other sections are available
+		for (int i = 0; i < leftContents.count(); ++i)
 		{
-			for (int i = 0; i < leftContents.count(); ++i)
+			const SectionContent::RefPtr sc = leftContents.at(i);
+			InternalContentData data;
+			this->takeContent(sc, data);
+
+			if (sections.isEmpty())
 			{
-				const SectionContent::RefPtr sc = leftContents.at(i);
-				InternalContentData data;
-				this->takeContent(sc, data);
-				sections.first()->addContent(sc);
+				HiddenSectionItem hsi;
+				hsi.data = data;
+				_hiddenSectionContents.insert(sc->uid(), hsi);
 			}
+			else
+				sections.first()->addContent(sc);
 		}
 	}
 
@@ -514,13 +632,34 @@ void ContainerWidget::saveSectionWidgets(QDataStream& out, QWidget* widget) cons
 	}
 	else if ((sw = dynamic_cast<SectionWidget*>(widget)) != NULL)
 	{
+		const QList<SectionContent::RefPtr>& contents = sw->contents();
+		QList<HiddenSectionItem> hiddenContents;
+
+		QHashIterator<int, HiddenSectionItem> iter(_hiddenSectionContents);
+		while (iter.hasNext())
+		{
+			iter.next();
+			const HiddenSectionItem& hsi = iter.value();
+			if (hsi.preferredSectionId != sw->uid())
+				continue;
+			hiddenContents.append(hsi);
+		}
+
 		out << 2; // Type = SectionWidget
 		out << sw->currentIndex();
-		out << sw->contents().count();
-		const QList<SectionContent::RefPtr>& contents = sw->contents();
+		out << contents.count() + hiddenContents.count();
+
 		for (int i = 0; i < contents.count(); ++i)
 		{
-			out << contents[i]->uniqueName();
+			out << contents[i]->uniqueName(); // Unique name
+			out << (bool) true; // Visiblity
+			out << i; // Index
+		}
+		for (int i = 0; i < hiddenContents.count(); ++i)
+		{
+			out << hiddenContents.at(i).data.content->uniqueName();
+			out << (bool) false;
+			out << hiddenContents.at(i).preferredSectionIndex;
 		}
 	}
 }
@@ -612,18 +751,30 @@ bool ContainerWidget::restoreSectionWidgets(QDataStream& in, QSplitter* currentS
 		{
 			QString uname;
 			in >> uname;
+			bool visible = false;
+			in >> visible;
+			int preferredIndex = -1;
+			in >> preferredIndex;
+
 			const SectionContent::RefPtr sc = SectionContent::LookupMapByName.value(uname).toStrongRef();
 			if (!sc)
 			{
 				qWarning() << "Can not find SectionContent:" << uname;
 				continue;
 			}
-
 			InternalContentData data;
-			if (!this->takeContent(sc, data))
-				continue;
+			this->takeContent(sc, data);
 
-			sw->addContent(sc);
+			if (visible)
+				sw->addContent(sc);
+			else
+			{
+				HiddenSectionItem hsi;
+				hsi.preferredSectionId = sw->uid();
+				hsi.preferredSectionIndex = preferredIndex;
+				hsi.data = data;
+				_hiddenSectionContents.insert(sc->uid(), hsi);
+			}
 		}
 		if (sw->contents().isEmpty())
 		{
@@ -672,7 +823,16 @@ void ContainerWidget::onActionToggleSectionContentVisibility(bool visible)
 	if (!a)
 		return;
 	const int uid = a->property("uid").toInt();
-	qDebug() << "Change visibility of" << uid << visible;
+	const SectionContent::RefPtr sc = SectionContent::LookupMap.value(uid).toStrongRef();
+	if (sc.isNull())
+	{
+		qCritical() << "Can not find content by ID" << uid;
+		return;
+	}
+	if (visible)
+		showSectionContent(sc);
+	else
+		hideSectionContent(sc);
 }
 
 ADS_NAMESPACE_END
diff --git a/AdvancedDockingSystem/src/SectionContentWidget.cpp b/AdvancedDockingSystem/src/SectionContentWidget.cpp
index 456020e..60db301 100644
--- a/AdvancedDockingSystem/src/SectionContentWidget.cpp
+++ b/AdvancedDockingSystem/src/SectionContentWidget.cpp
@@ -1,5 +1,6 @@
 #include "ads/SectionContentWidget.h"
 
+#include <QDebug>
 #include <QBoxLayout>
 
 ADS_NAMESPACE_BEGIN
@@ -15,4 +16,9 @@ SectionContentWidget::SectionContentWidget(SectionContent::RefPtr c, QWidget* pa
 	setLayout(l);
 }
 
+SectionContentWidget::~SectionContentWidget()
+{
+	qDebug() << Q_FUNC_INFO;
+}
+
 ADS_NAMESPACE_END
diff --git a/AdvancedDockingSystem/src/SectionTitleWidget.cpp b/AdvancedDockingSystem/src/SectionTitleWidget.cpp
index be81ba4..28434a0 100644
--- a/AdvancedDockingSystem/src/SectionTitleWidget.cpp
+++ b/AdvancedDockingSystem/src/SectionTitleWidget.cpp
@@ -38,6 +38,11 @@ SectionTitleWidget::SectionTitleWidget(SectionContent::RefPtr content, QWidget*
 	setLayout(l);
 }
 
+SectionTitleWidget::~SectionTitleWidget()
+{
+	qDebug() << Q_FUNC_INFO;
+}
+
 bool SectionTitleWidget::isActiveTab() const
 {
 	return _activeTab;
diff --git a/AdvancedDockingSystem/src/SectionWidget.cpp b/AdvancedDockingSystem/src/SectionWidget.cpp
index c6461f4..7be3931 100644
--- a/AdvancedDockingSystem/src/SectionWidget.cpp
+++ b/AdvancedDockingSystem/src/SectionWidget.cpp
@@ -9,6 +9,7 @@
 #include <QPainter>
 #include <QStyle>
 #include <QSplitter>
+#include <QPushButton>
 
 #if defined(ADS_ANIMATIONS_ENABLED)
 #include <QGraphicsDropShadowEffect>
@@ -31,7 +32,10 @@ QHash<ContainerWidget*, QHash<int, SectionWidget*> > SectionWidget::LookupMapByC
 SectionWidget::SectionWidget(ContainerWidget* parent) :
 	QFrame(parent),
 	_uid(NextUid++),
-	_container(parent)
+	_container(parent),
+	_tabsLayout(NULL),
+	_contentsLayout(NULL),
+	_mousePressTitleWidget(NULL)
 {
 	QBoxLayout* l = new QBoxLayout(QBoxLayout::TopToBottom);
 	l->setContentsMargins(0, 0, 0, 0);
@@ -44,6 +48,19 @@ SectionWidget::SectionWidget(ContainerWidget* parent) :
 	_tabsLayout->addStretch(1);
 	l->addLayout(_tabsLayout);
 
+	QPushButton* closeButton = new QPushButton();
+	closeButton->setObjectName("closeButton");
+	closeButton->setFlat(true);
+	closeButton->setIcon(style()->standardIcon(QStyle::SP_TitleBarCloseButton));
+	closeButton->setToolTip(tr("Close"));
+	closeButton->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
+	_tabsLayout->addWidget(closeButton);
+#if QT_VERSION >= 0x050000
+	QObject::connect(closeButton, &QPushButton::clicked, this, &SectionWidget::onCloseButtonClicked);
+#else
+	QObject::connect(closeButton, SIGNAL(clicked(bool)), this, SLOT(onCloseButtonClicked()));
+#endif
+
 	_contentsLayout = new QStackedLayout();
 	_contentsLayout->setContentsMargins(0, 0, 0, 0);
 	_contentsLayout->setSpacing(0);
@@ -58,7 +75,6 @@ SectionWidget::SectionWidget(ContainerWidget* parent) :
 
 	LookupMap.insert(_uid, this);
 	LookupMapByContainer[_container].insert(_uid, this);
-//	_container->_sections.append(this);
 }
 
 SectionWidget::~SectionWidget()
@@ -97,13 +113,13 @@ QRect SectionWidget::contentAreaGeometry() const
 	return _contentsLayout->geometry();
 }
 
-void SectionWidget::addContent(SectionContent::RefPtr c)
+void SectionWidget::addContent(const SectionContent::RefPtr& c)
 {
 	_contents.append(c);
 
 	SectionTitleWidget* title = new SectionTitleWidget(c, NULL);
 	_sectionTitles.append(title);
-	_tabsLayout->insertWidget(_tabsLayout->count() - 1, title);
+	_tabsLayout->insertWidget(_tabsLayout->count() - 2, title);
 #if QT_VERSION >= 0x050000
 	QObject::connect(title, &SectionTitleWidget::clicked, this, &SectionWidget::onSectionTitleClicked);
 #else
@@ -127,7 +143,7 @@ void SectionWidget::addContent(const InternalContentData& data, bool autoActivat
 	_contents.append(data.content);
 
 	_sectionTitles.append(data.titleWidget);
-	_tabsLayout->insertWidget(_tabsLayout->count() - 1, data.titleWidget);
+	_tabsLayout->insertWidget(_tabsLayout->count() - 2, data.titleWidget);
 #if QT_VERSION >= 0x050000
 	QObject::connect(data.titleWidget, &SectionTitleWidget::clicked, this, &SectionWidget::onSectionTitleClicked);
 #else
@@ -142,12 +158,9 @@ void SectionWidget::addContent(const InternalContentData& data, bool autoActivat
 		setCurrentIndex(0);
 	// Switch to newest.
 	else if (autoActivate)
-		setCurrentIndex(_contentsLayout->count() - 1);
+		setCurrentIndex(_contents.count() - 1);
 }
 
-// take removes a widget from the SectionWidget but does not delete
-// the used SectionTitle- and SectionContent-Widget. Instead it returns
-// these objects.
 bool SectionWidget::takeContent(int uid, InternalContentData& data)
 {
 	// Find SectionContent.
@@ -170,6 +183,7 @@ bool SectionWidget::takeContent(int uid, InternalContentData& data)
 	{
 		_tabsLayout->removeWidget(title);
 		title->disconnect(this);
+		title->setParent(_container);
 	}
 
 	// Content wrapper widget (CONTENT)
@@ -178,6 +192,7 @@ bool SectionWidget::takeContent(int uid, InternalContentData& data)
 	{
 		_contentsLayout->removeWidget(content);
 		content->disconnect(this);
+		content->setParent(_container);
 	}
 
 	// Select the previous tab as activeTab.
@@ -195,7 +210,7 @@ bool SectionWidget::takeContent(int uid, InternalContentData& data)
 	return !data.content.isNull();
 }
 
-int SectionWidget::indexOfContent(SectionContent::RefPtr c) const
+int SectionWidget::indexOfContent(const SectionContent::RefPtr& c) const
 {
 	return _contents.indexOf(c);
 }
@@ -258,10 +273,13 @@ void SectionWidget::setCurrentIndex(int index)
 		if (item->widget())
 		{
 			SectionTitleWidget* stw = dynamic_cast<SectionTitleWidget*>(item->widget());
-			if (i == index)
-				stw->setActiveTab(true);
-			else
-				stw->setActiveTab(false);
+			if (stw)
+			{
+				if (i == index)
+					stw->setActiveTab(true);
+				else
+					stw->setActiveTab(false);
+			}
 		}
 	}
 
@@ -269,15 +287,6 @@ void SectionWidget::setCurrentIndex(int index)
 	_contentsLayout->setCurrentIndex(index);
 }
 
-void SectionWidget::paintEvent(QPaintEvent* e)
-{
-	QFrame::paintEvent(e);
-
-//	QPainter p(this);
-//	auto r = rect();
-//	p.drawText(rect(), Qt::AlignCenter | Qt::AlignVCenter, QString("x=%1; y=%2; w=%3; h=%4").arg(r.x()).arg(r.y()).arg(r.width()).arg(r.height()));
-}
-
 void SectionWidget::onSectionTitleClicked()
 {
 	SectionTitleWidget* stw = qobject_cast<SectionTitleWidget*>(sender());
@@ -288,4 +297,16 @@ void SectionWidget::onSectionTitleClicked()
 	}
 }
 
+void SectionWidget::onCloseButtonClicked()
+{
+	qDebug() << Q_FUNC_INFO << currentIndex();
+	const int index = currentIndex();
+	if (index < 0 || index > _contents.size() - 1)
+		return;
+	SectionContent::RefPtr sc = _contents.at(index);
+	if (sc.isNull())
+		return;
+	_container->hideSectionContent(sc);
+}
+
 ADS_NAMESPACE_END
diff --git a/README.md b/README.md
index 32e17ef..8edcfe4 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,10 @@ Basic usage of QWidgets an QLayouts and using basic styles as much as possible.
 ## Build
 Open the `build.pro` with QtCreator and start the build, that's it.
 
+## Release & Development
+The master branch is not guaranteed to be stable or does even build, since it is the main working branch.
+If you want a version that builds you should always use a release/beta tag.
+
 ## Notes
 - *SectionContent* class may safe a "size-type" property, which defines how the size of the widget should be handled.
 	- PerCent: Resize in proportion to other widgets.
@@ -34,6 +38,8 @@ Sorted by priority
 - [x] Working with outer-edge-drops sometimes leaves empty splitters #BUG
 - [x] Clean up of unused e.g. count()<=1 QSplitters doesn't work well #BUG
 - [ ] Show close button on right corner of SectionWidget. How to safe last section position?
+- [ ] Serialize state of `_hiddenSectionContents`
+- [ ] `ContainerWidget::showSectionContent` needs to insert the SC at the correct preferred position of SW
 - [ ] Empty splitters, if only 2 or 1 items are in container
 
 ### Some day...