diff --git a/src/plugins/help/CMakeLists.txt b/src/plugins/help/CMakeLists.txt
index 76a680c7595..c25f0b6cd5b 100644
--- a/src/plugins/help/CMakeLists.txt
+++ b/src/plugins/help/CMakeLists.txt
@@ -12,7 +12,6 @@ add_qtc_plugin(Help
     helpfindsupport.cpp helpfindsupport.h
     helpindexfilter.cpp helpindexfilter.h
     helpmanager.cpp helpmanager.h
-    helpmode.cpp helpmode.h
     helpplugin.cpp helpplugin.h
     helpviewer.cpp helpviewer.h
     helpwidget.cpp helpwidget.h
diff --git a/src/plugins/help/help.qbs b/src/plugins/help/help.qbs
index 25d85bdc37e..d96cfa154e7 100644
--- a/src/plugins/help/help.qbs
+++ b/src/plugins/help/help.qbs
@@ -43,7 +43,6 @@ Project {
                 "helpfindsupport.cpp", "helpfindsupport.h",
                 "helpindexfilter.cpp", "helpindexfilter.h",
                 "helpmanager.cpp", "helpmanager.h",
-                "helpmode.cpp", "helpmode.h",
                 "helpplugin.cpp", "helpplugin.h",
                 "helpviewer.cpp", "helpviewer.h",
                 "helpwidget.cpp", "helpwidget.h",
diff --git a/src/plugins/help/helpmode.cpp b/src/plugins/help/helpmode.cpp
deleted file mode 100644
index 2e2ee468939..00000000000
--- a/src/plugins/help/helpmode.cpp
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
-
-#include "helpmode.h"
-#include "helpconstants.h"
-#include "helpicons.h"
-#include "helptr.h"
-
-#include <QCoreApplication>
-
-using namespace Help;
-using namespace Help::Internal;
-
-HelpMode::HelpMode(QObject *parent)
-  : Core::IMode(parent)
-{
-    setObjectName("HelpMode");
-    setContext(Core::Context(Constants::C_MODE_HELP));
-    setIcon(Utils::Icon::modeIcon(Icons::MODE_HELP_CLASSIC,
-                                  Icons::MODE_HELP_FLAT, Icons::MODE_HELP_FLAT_ACTIVE));
-    setDisplayName(Tr::tr("Help"));
-    setPriority(Constants::P_MODE_HELP);
-    setId(Constants::ID_MODE_HELP);
-}
diff --git a/src/plugins/help/helpmode.h b/src/plugins/help/helpmode.h
deleted file mode 100644
index fbe69f08bca..00000000000
--- a/src/plugins/help/helpmode.h
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
-
-#pragma once
-
-#include <coreplugin/imode.h>
-
-#include <QString>
-#include <QIcon>
-
-namespace Help {
-namespace Internal {
-
-class HelpMode : public Core::IMode
-{
-public:
-    explicit HelpMode(QObject *parent = nullptr);
-};
-
-} // namespace Internal
-} // namespace Help
diff --git a/src/plugins/help/helpplugin.cpp b/src/plugins/help/helpplugin.cpp
index 56126372476..de055889edb 100644
--- a/src/plugins/help/helpplugin.cpp
+++ b/src/plugins/help/helpplugin.cpp
@@ -4,7 +4,6 @@
 #include "helpplugin.h"
 
 #include "bookmarkmanager.h"
-#include "contentwindow.h"
 #include "docsettingspage.h"
 #include "filtersettingspage.h"
 #include "generalsettingspage.h"
@@ -13,11 +12,9 @@
 #include "helpicons.h"
 #include "helpindexfilter.h"
 #include "helpmanager.h"
-#include "helpmode.h"
 #include "helptr.h"
 #include "helpviewer.h"
 #include "helpwidget.h"
-#include "indexwindow.h"
 #include "localhelpmanager.h"
 #include "openpagesmanager.h"
 #include "searchtaskhandler.h"
@@ -35,6 +32,7 @@
 #include <coreplugin/findplaceholder.h>
 #include <coreplugin/helpitem.h>
 #include <coreplugin/icore.h>
+#include <coreplugin/imode.h>
 #include <coreplugin/minisplitter.h>
 #include <coreplugin/modemanager.h>
 #include <coreplugin/rightpane.h>
@@ -52,38 +50,47 @@
 #include <utils/theme/theme.h>
 #include <utils/tooltip/tooltip.h>
 
-#include <QApplication>
-#include <QDialog>
-#include <QDialogButtonBox>
-#include <QDir>
-#include <QFileInfo>
-#include <QLabel>
-#include <QLibraryInfo>
-#include <QPlainTextEdit>
-#include <QTimer>
-#include <QTranslator>
-#include <qplugin.h>
-#include <QRegularExpression>
-
 #include <QAction>
+#include <QApplication>
 #include <QComboBox>
 #include <QDesktopServices>
-#include <QMenu>
-#include <QStackedLayout>
-#include <QSplitter>
-
+#include <QDialog>
+#include <QDialogButtonBox>
 #include <QHelpEngine>
+#include <QLabel>
+#include <QLibraryInfo>
+#include <QMenu>
+#include <QPlainTextEdit>
+#include <QRegularExpression>
+#include <QSplitter>
+#include <QStackedLayout>
+#include <QTimer>
+#include <QTranslator>
 
 #include <functional>
 
-static const char kExternalWindowStateKey[] = "Help/ExternalWindowState";
-static const char kToolTipHelpContext[] = "Help.ToolTip";
-
 using namespace Core;
 using namespace Utils;
 
-namespace Help {
-namespace Internal {
+namespace Help::Internal {
+
+const char kExternalWindowStateKey[] = "Help/ExternalWindowState";
+const char kToolTipHelpContext[] = "Help.ToolTip";
+
+class HelpMode : public IMode
+{
+public:
+    HelpMode()
+    {
+        setObjectName("HelpMode");
+        setContext(Core::Context(Constants::C_MODE_HELP));
+        setIcon(Icon::modeIcon(Icons::MODE_HELP_CLASSIC,
+                               Icons::MODE_HELP_FLAT, Icons::MODE_HELP_FLAT_ACTIVE));
+        setDisplayName(Tr::tr("Help"));
+        setPriority(Constants::P_MODE_HELP);
+        setId(Constants::ID_MODE_HELP);
+    }
+};
 
 class HelpPluginPrivate : public QObject
 {
@@ -641,5 +648,4 @@ void HelpPluginPrivate::doSetupIfNeeded()
     }
 }
 
-} // Internal
-} // Help
+} // Help::Internal