diff --git a/src/plugins/coreplugin/outputwindow.cpp b/src/plugins/coreplugin/outputwindow.cpp
index 1417eb1e3d8..344d117e4fa 100644
--- a/src/plugins/coreplugin/outputwindow.cpp
+++ b/src/plugins/coreplugin/outputwindow.cpp
@@ -36,11 +36,13 @@
 
 #include <QAction>
 #include <QCursor>
+#include <QElapsedTimer>
 #include <QMimeData>
 #include <QPointer>
 #include <QRegularExpression>
 #include <QScrollBar>
 #include <QTextBlock>
+#include <QTimer>
 
 #ifdef WITH_TESTS
 #include <QtTest>
@@ -89,6 +91,8 @@ public:
     int lastFilteredBlockNumber = -1;
     QPalette originalPalette;
     OutputWindow::FilterModeFlags filterMode = OutputWindow::FilterModeFlag::Default;
+    QTimer scrollTimer;
+    QElapsedTimer lastMessage;
 };
 
 } // namespace Internal
@@ -161,11 +165,11 @@ OutputWindow::OutputWindow(Context context, const QString &settingsKey, QWidget
     cutAction->setEnabled(false);
     copyAction->setEnabled(false);
 
-    m_scrollTimer.setInterval(10);
-    m_scrollTimer.setSingleShot(true);
-    connect(&m_scrollTimer, &QTimer::timeout,
+    d->scrollTimer.setInterval(10);
+    d->scrollTimer.setSingleShot(true);
+    connect(&d->scrollTimer, &QTimer::timeout,
             this, &OutputWindow::scrollToBottom);
-    m_lastMessage.start();
+    d->lastMessage.start();
 
     d->originalFontSize = font().pointSizeF();
 
@@ -426,20 +430,20 @@ void OutputWindow::handleOutputChunk(const QString &output, OutputFormat format)
         }
     }
 
-    const bool atBottom = isScrollbarAtBottom() || m_scrollTimer.isActive();
+    const bool atBottom = isScrollbarAtBottom() || d->scrollTimer.isActive();
     d->scrollToBottom = true;
     d->formatter.appendMessage(out, format);
 
     if (atBottom) {
-        if (m_lastMessage.elapsed() < 5) {
-            m_scrollTimer.start();
+        if (d->lastMessage.elapsed() < 5) {
+            d->scrollTimer.start();
         } else {
-            m_scrollTimer.stop();
+            d->scrollTimer.stop();
             scrollToBottom();
         }
     }
 
-    m_lastMessage.start();
+    d->lastMessage.start();
     enableUndoRedo();
 }
 
diff --git a/src/plugins/coreplugin/outputwindow.h b/src/plugins/coreplugin/outputwindow.h
index d717fbe4f63..91a69d20421 100644
--- a/src/plugins/coreplugin/outputwindow.h
+++ b/src/plugins/coreplugin/outputwindow.h
@@ -30,9 +30,7 @@
 
 #include <utils/outputformat.h>
 
-#include <QElapsedTimer>
 #include <QPlainTextEdit>
-#include <QTimer>
 
 namespace Utils {
 class OutputFormatter;
@@ -106,8 +104,6 @@ private:
     void wheelEvent(QWheelEvent *e) override;
 
     using QPlainTextEdit::setFont; // call setBaseFont instead, which respects the zoom factor
-    QTimer m_scrollTimer;
-    QElapsedTimer m_lastMessage;
     void enableUndoRedo();
     void filterNewContent();
     void handleNextOutputChunk();
diff --git a/src/plugins/projectexplorer/appoutputpane.cpp b/src/plugins/projectexplorer/appoutputpane.cpp
index 83877266d04..de92f588cb0 100644
--- a/src/plugins/projectexplorer/appoutputpane.cpp
+++ b/src/plugins/projectexplorer/appoutputpane.cpp
@@ -60,6 +60,7 @@
 #include <QSpinBox>
 #include <QTabBar>
 #include <QTabWidget>
+#include <QTimer>
 #include <QToolButton>
 #include <QVBoxLayout>