diff --git a/src/widgets/widgets/qplaintextedit.cpp b/src/widgets/widgets/qplaintextedit.cpp
index 68be945f46..2b91ca2ecb 100644
--- a/src/widgets/widgets/qplaintextedit.cpp
+++ b/src/widgets/widgets/qplaintextedit.cpp
@@ -755,22 +755,12 @@ void QPlainTextEditPrivate::updateViewport()
 }
 
 QPlainTextEditPrivate::QPlainTextEditPrivate()
-    : control(nullptr),
-      tabChangesFocus(false),
-      lineWrap(QPlainTextEdit::WidgetWidth),
-      wordWrap(QTextOption::WrapAtWordBoundaryOrAnywhere),
-      keyboardModifiers{},
-      clickCausedFocus(0), placeholderVisible(1),
-      topLine(0), topLineFracture(0),
+    : tabChangesFocus(false), showCursorOnInitialShow(false), backgroundVisible(false),
+      centerOnScroll(false), inDrag(false), clickCausedFocus(false), placeholderVisible(true),
       pageUpDownLastCursorYIsValid(false)
 {
-    showCursorOnInitialShow = true;
-    backgroundVisible = false;
-    centerOnScroll = false;
-    inDrag = false;
 }
 
-
 void QPlainTextEditPrivate::init(const QString &txt)
 {
     Q_Q(QPlainTextEdit);
@@ -825,7 +815,6 @@ void QPlainTextEditPrivate::init(const QString &txt)
 #ifndef QT_NO_CURSOR
     viewport->setCursor(Qt::IBeamCursor);
 #endif
-    originalOffsetY = 0;
 }
 
 void QPlainTextEditPrivate::_q_textChanged()
diff --git a/src/widgets/widgets/qplaintextedit_p.h b/src/widgets/widgets/qplaintextedit_p.h
index 6d82cabb93..112eb2e4f6 100644
--- a/src/widgets/widgets/qplaintextedit_p.h
+++ b/src/widgets/widgets/qplaintextedit_p.h
@@ -143,26 +143,30 @@ public:
 
     void updateDefaultTextOption();
 
-    QPlainTextEditControl *control;
-
-    bool tabChangesFocus;
-
     QBasicTimer autoScrollTimer;
+#ifdef QT_KEYPAD_NAVIGATION
+    QBasicTimer deleteAllTimer;
+#endif
     QPoint autoScrollDragPos;
+    QString placeholderText;
 
-    QPlainTextEdit::LineWrapMode lineWrap;
-    QTextOption::WrapMode wordWrap;
-    Qt::KeyboardModifiers keyboardModifiers;
+    QPlainTextEditControl *control = nullptr;
+    qreal topLineFracture = 0; // for non-int sized fonts
+    qreal pageUpDownLastCursorY = 0;
+    QPlainTextEdit::LineWrapMode lineWrap = QPlainTextEdit::WidgetWidth;
+    QTextOption::WrapMode wordWrap = QTextOption::WrapAtWordBoundaryOrAnywhere;
+    Qt::KeyboardModifiers keyboardModifiers = {};
+    int originalOffsetY = 0;
+    int topLine = 0;
 
+    uint tabChangesFocus : 1;
     uint showCursorOnInitialShow : 1;
     uint backgroundVisible : 1;
     uint centerOnScroll : 1;
     uint inDrag : 1;
     uint clickCausedFocus : 1;
     uint placeholderVisible : 1;
-
-    int topLine;
-    qreal topLineFracture; // for non-int sized fonts
+    uint pageUpDownLastCursorYIsValid : 1;
 
     void setTopLine(int visualTopLine, int dx = 0);
     void setTopBlock(int newTopBlock, int newTopLine, int dx = 0);
@@ -175,19 +179,8 @@ public:
 
     void append(const QString &text, Qt::TextFormat format = Qt::AutoText);
 
-    qreal pageUpDownLastCursorY;
-    bool pageUpDownLastCursorYIsValid;
-
-
-#ifdef QT_KEYPAD_NAVIGATION
-    QBasicTimer deleteAllTimer;
-#endif
-
     void _q_cursorPositionChanged();
     void _q_modificationChanged(bool);
-
-    int originalOffsetY;
-    QString placeholderText;
 };
 
 QT_END_NAMESPACE
diff --git a/src/widgets/widgets/qtabbar_p.h b/src/widgets/widgets/qtabbar_p.h
index 4d005af9a9..1036d819eb 100644
--- a/src/widgets/widgets/qtabbar_p.h
+++ b/src/widgets/widgets/qtabbar_p.h
@@ -88,43 +88,60 @@ class Q_WIDGETS_EXPORT QTabBarPrivate : public QWidgetPrivate
     Q_DECLARE_PUBLIC(QTabBar)
 public:
     QTabBarPrivate()
-        : currentIndex(-1), mouseButtons(Qt::NoButton), pressedIndex(-1), firstVisible(0), lastVisible(-1),
-        shape(QTabBar::RoundedNorth), layoutDirty(false), drawBase(true), scrollOffset(0),
-        hoverIndex(-1), elideModeSetByUser(false), useScrollButtonsSetByUser(false), expanding(true),
-        closeButtonOnTabs(false), selectionBehaviorOnRemove(QTabBar::SelectRightTab),
-        paintWithOffsets(true), movable(false), dragInProgress(false), documentMode(false),
-        autoHide(false), changeCurrentOnDrag(false), switchTabCurrentIndex(-1), switchTabTimerId(0),
-        movingTab(nullptr)
-        {}
+    : layoutDirty(false), drawBase(true), elideModeSetByUser(false), useScrollButtons(false),
+      useScrollButtonsSetByUser(false), expanding(true), closeButtonOnTabs(false),
+      paintWithOffsets(true), movable(false), dragInProgress(false), documentMode(false),
+      autoHide(false), changeCurrentOnDrag(false)
+    {}
 
-    int currentIndex;
-    Qt::MouseButtons mouseButtons;
-    int pressedIndex;
-    int firstVisible;
-    int lastVisible;
-    QTabBar::Shape shape;
-    bool layoutDirty;
-    bool drawBase;
-    int scrollOffset;
+    QRect hoverRect;
+    QPoint dragStartPosition;
+    QSize iconSize;
+    QToolButton* rightB = nullptr; // right or bottom
+    QToolButton* leftB = nullptr; // left or top
+    QMovableTabWidget *movingTab = nullptr;
+    int hoverIndex = -1;
+    int switchTabCurrentIndex = -1;
+    int switchTabTimerId = 0;
+    Qt::TextElideMode elideMode = Qt::ElideNone;
+    QTabBar::SelectionBehavior selectionBehaviorOnRemove = QTabBar::SelectRightTab;
+    QTabBar::Shape shape = QTabBar::RoundedNorth;
+    Qt::MouseButtons mouseButtons = Qt::NoButton;
+
+    int currentIndex = -1;
+    int pressedIndex = -1;
+    int firstVisible = 0;
+    int lastVisible = -1;
+    int scrollOffset = 0;
+
+    bool layoutDirty : 1;
+    bool drawBase : 1;
+    bool elideModeSetByUser : 1;
+    bool useScrollButtons : 1;
+    bool useScrollButtonsSetByUser : 1;
+    bool expanding : 1;
+    bool closeButtonOnTabs : 1;
+    bool paintWithOffsets : 1;
+    bool movable : 1;
+    bool dragInProgress : 1;
+    bool documentMode : 1;
+    bool autoHide : 1;
+    bool changeCurrentOnDrag : 1;
 
     struct Tab {
         inline Tab(const QIcon &ico, const QString &txt)
-            : enabled(true) , visible(true), shortcutId(0), text(txt), icon(ico),
-            leftWidget(nullptr), rightWidget(nullptr), lastTab(-1), dragOffset(0)
-#if QT_CONFIG(animation)
-            , animation(nullptr)
-#endif // animation
+        : text(txt), icon(ico), enabled(true), visible(true)
         {}
         bool operator==(const Tab &other) const { return &other == this; }
-        bool enabled;
-        bool visible;
-        int shortcutId;
         QString text;
 #if QT_CONFIG(tooltip)
         QString toolTip;
 #endif
 #if QT_CONFIG(whatsthis)
         QString whatsThis;
+#endif
+#ifndef QT_NO_ACCESSIBILITY
+        QString accessibleName;
 #endif
         QIcon icon;
         QRect rect;
@@ -133,13 +150,13 @@ public:
 
         QColor textColor;
         QVariant data;
-        QWidget *leftWidget;
-        QWidget *rightWidget;
-        int lastTab;
-        int dragOffset;
-#ifndef QT_NO_ACCESSIBILITY
-        QString accessibleName;
-#endif
+        QWidget *leftWidget = nullptr;
+        QWidget *rightWidget = nullptr;
+        int shortcutId = 0;
+        int lastTab = -1;
+        int dragOffset = 0;
+        uint enabled : 1;
+        uint visible : 1;
 
 #if QT_CONFIG(animation)
         ~Tab() { delete animation; }
@@ -154,7 +171,7 @@ public:
             //these are needed for the callbacks
             Tab *tab;
             QTabBarPrivate *priv;
-        } *animation;
+        } *animation = nullptr;
 
         void startAnimation(QTabBarPrivate *priv, int duration) {
             if (!priv->isAnimated()) {
@@ -191,15 +208,10 @@ public:
     inline bool validIndex(int index) const { return index >= 0 && index < tabList.count(); }
     void setCurrentNextEnabledIndex(int offset);
 
-    QToolButton* rightB; // right or bottom
-    QToolButton* leftB; // left or top
-
     void _q_scrollTabs();
     void _q_closeTab();
     void moveTab(int index, int offset);
     void moveTabFinished(int index);
-    QRect hoverRect;
-    int hoverIndex;
 
     void refresh();
     void layoutTabs();
@@ -215,28 +227,7 @@ public:
     void initBasicStyleOption(QStyleOptionTab *option, int tabIndex) const;
 
     void makeVisible(int index);
-    QSize iconSize;
-    Qt::TextElideMode elideMode;
-    bool elideModeSetByUser;
-    bool useScrollButtons;
-    bool useScrollButtonsSetByUser;
 
-    bool expanding;
-    bool closeButtonOnTabs;
-    QTabBar::SelectionBehavior selectionBehaviorOnRemove;
-
-    QPoint dragStartPosition;
-    bool paintWithOffsets;
-    bool movable;
-    bool dragInProgress;
-    bool documentMode;
-    bool autoHide;
-    bool changeCurrentOnDrag;
-
-    int switchTabCurrentIndex;
-    int switchTabTimerId;
-
-    QMovableTabWidget *movingTab;
     // shared by tabwidget and qtabbar
     static void initStyleBaseOption(QStyleOptionTabBarBase *optTabBase, QTabBar *tabbar, QSize size)
     {