diff --git a/include/audacity/ComponentInterface.h b/include/audacity/ComponentInterface.h
index e17497dae..28499e2cf 100644
--- a/include/audacity/ComponentInterface.h
+++ b/include/audacity/ComponentInterface.h
@@ -43,6 +43,8 @@
 #define __AUDACITY_COMPONENT_INTERFACE_H__
 
 #include "audacity/Types.h"
+#include <wx/string.h> // member variables
+
 extern AUDACITY_DLL_API const wxString& GetCustomTranslation(const wxString& str1 );
 
 /**************************************************************************//**
diff --git a/include/audacity/Types.h b/include/audacity/Types.h
index 172ff0d67..985435322 100644
--- a/include/audacity/Types.h
+++ b/include/audacity/Types.h
@@ -43,9 +43,11 @@
 #define __AUDACITY_TYPES_H__
 
 #include <algorithm>
-#include <wx/arrstr.h>
 #include <type_traits>
 #include <vector>
+#include <wx/debug.h> // for wxASSERT
+
+class wxString;
 
 // ----------------------------------------------------------------------------
 // TODO:  I'd imagine this header may be replaced by other public headers. But,
diff --git a/src/AudioIO.h b/src/AudioIO.h
index 08d8dc3c5..7be8bcf3d 100644
--- a/src/AudioIO.h
+++ b/src/AudioIO.h
@@ -53,6 +53,7 @@ using NoteTrackConstArray = std::vector < std::shared_ptr< const NoteTrack > >;
 
 #include "SampleFormat.h"
 
+class wxArrayString;
 class AudioIO;
 class RingBuffer;
 class Mixer;
diff --git a/src/BatchCommands.h b/src/BatchCommands.h
index a7a7b3bd7..1dee0f74f 100644
--- a/src/BatchCommands.h
+++ b/src/BatchCommands.h
@@ -16,6 +16,7 @@
 
 #include "export/Export.h"
 
+class wxArrayString;
 class Effect;
 class CommandContext;
 class AudacityProject;
diff --git a/src/FileFormats.h b/src/FileFormats.h
index b47e3ecec..646a5f807 100644
--- a/src/FileFormats.h
+++ b/src/FileFormats.h
@@ -14,7 +14,6 @@
 #include "Audacity.h" // for __UNIX__
 
 #include <wx/list.h>
-#include <wx/arrstr.h>
 
 #include "audacity/Types.h"
 
diff --git a/src/FileNames.h b/src/FileNames.h
index 320785c2b..f4b427393 100644
--- a/src/FileNames.h
+++ b/src/FileNames.h
@@ -13,11 +13,11 @@
 
 #include "Audacity.h"
 
+#include <wx/string.h> // function return value
 #include "audacity/Types.h"
 
 class wxFileName;
 class wxFileNameWrapper;
-class wxArrayString;
 
 // Uh, this is really a namespace rather than a class,
 // since all the functions are static.
diff --git a/src/LabelDialog.h b/src/LabelDialog.h
index d2d79e287..914a8ce72 100644
--- a/src/LabelDialog.h
+++ b/src/LabelDialog.h
@@ -20,6 +20,7 @@
 #include "widgets/Grid.h"
 #include "widgets/wxPanelWrapper.h"
 
+class wxArrayString;
 class TrackFactory;
 class TrackList;
 class RowData;
diff --git a/src/Languages.h b/src/Languages.h
index 86c38ce60..8f7edbba0 100644
--- a/src/Languages.h
+++ b/src/Languages.h
@@ -11,7 +11,8 @@
 #ifndef __AUDACITY_LANGUAGES__
 #define __AUDACITY_LANGUAGES__
 
-#include <wx/arrstr.h>
+class wxArrayString;
+
 #include <wx/list.h>
 
 void GetLanguages(wxArrayString &langCodes, wxArrayString &langNames);
diff --git a/src/Menus.h b/src/Menus.h
index 550a5e856..31b719856 100644
--- a/src/Menus.h
+++ b/src/Menus.h
@@ -12,8 +12,9 @@
 
 #include "audacity/Types.h"
 
-#include <wx/arrstr.h>
+#include <wx/string.h> // member variable
 
+class wxArrayString;
 class AudacityProject;
 class CommandContext;
 class CommandManager;
diff --git a/src/MixerBoard.h b/src/MixerBoard.h
index 020426b6f..aeab2f86a 100644
--- a/src/MixerBoard.h
+++ b/src/MixerBoard.h
@@ -27,6 +27,7 @@
 #include "widgets/wxPanelWrapper.h"
 #include "commands/CommandManagerWindowClasses.h"
 
+class wxArrayString;
 struct TrackListEvent;
 
 // containment hierarchy:
diff --git a/src/ModuleManager.h b/src/ModuleManager.h
index 1a1649c04..30c742ae5 100644
--- a/src/ModuleManager.h
+++ b/src/ModuleManager.h
@@ -20,6 +20,7 @@
 
 #include "audacity/ModuleInterface.h"
 
+class wxArrayString;
 class CommandHandler;
 
 wxWindow *  MakeHijackPanel();
diff --git a/src/PluginManager.h b/src/PluginManager.h
index 25be8074b..55a9c58fb 100644
--- a/src/PluginManager.h
+++ b/src/PluginManager.h
@@ -22,6 +22,8 @@
 #include "audacity/ModuleInterface.h"
 #include "audacity/PluginInterface.h"
 
+class wxArrayString;
+
 ///////////////////////////////////////////////////////////////////////////////
 //
 // PluginDescriptor
diff --git a/src/Project.h b/src/Project.h
index f328ecb90..ab447d9ce 100644
--- a/src/Project.h
+++ b/src/Project.h
@@ -47,6 +47,7 @@
 
 const int AudacityProjectTimerID = 5200;
 
+class wxArrayString;
 class wxWindow;
 class wxDialog;
 class wxBoxSizer;
diff --git a/src/Tags.h b/src/Tags.h
index 1111a8461..83c725ff1 100644
--- a/src/Tags.h
+++ b/src/Tags.h
@@ -43,6 +43,7 @@
 
 #include <unordered_map>
 
+class wxArrayString;
 class wxButton;
 class wxChoice;
 class wxComboBox;
diff --git a/src/Theme.h b/src/Theme.h
index 82b5d56b3..9c8b5aff0 100644
--- a/src/Theme.h
+++ b/src/Theme.h
@@ -24,6 +24,8 @@
 #include <wx/image.h>
 #include <wx/window.h> // to inherit
 
+class wxArrayString;
+
 // JKC: will probably change name from 'teBmps' to 'tIndexBmp';
 typedef int teBmps; /// The index of a bitmap resource in Theme Resources.
 
diff --git a/src/commands/CommandManager.h b/src/commands/CommandManager.h
index dffe8c758..c21c75632 100644
--- a/src/commands/CommandManager.h
+++ b/src/commands/CommandManager.h
@@ -32,6 +32,7 @@
 
 class wxMenu;
 class wxMenuBar;
+class wxArrayString;
 class TranslatedInternalString;
 using CommandParameter = CommandID;
 
diff --git a/src/commands/Validators.h b/src/commands/Validators.h
index 25e904e6c..2309ac2d1 100644
--- a/src/commands/Validators.h
+++ b/src/commands/Validators.h
@@ -43,6 +43,8 @@ a certain criterion. This is a base validator which allows anything.
 #ifndef __VALIDATORS__
 #define __VALIDATORS__
 
+class wxArrayString;
+
 #include "../MemoryX.h"
 
 class Validator /* not final */
diff --git a/src/effects/Distortion.h b/src/effects/Distortion.h
index 892c45f7c..adf69405d 100644
--- a/src/effects/Distortion.h
+++ b/src/effects/Distortion.h
@@ -11,7 +11,6 @@
 #ifndef __AUDACITY_EFFECT_DISTORTION__
 #define __AUDACITY_EFFECT_DISTORTION__
 
-#include <wx/arrstr.h>
 #include <wx/slider.h>
 #include <wx/textctrl.h>
 #include <wx/checkbox.h>
diff --git a/src/effects/Effect.h b/src/effects/Effect.h
index f27546aa8..91a9a1cc4 100644
--- a/src/effects/Effect.h
+++ b/src/effects/Effect.h
@@ -41,6 +41,7 @@ class wxWindow;
 
 #include "../Track.h"
 
+class wxArrayString;
 class ShuttleGui;
 class AudacityCommand;
 
diff --git a/src/effects/ScienFilter.h b/src/effects/ScienFilter.h
index 63b3b039d..f40f54e92 100644
--- a/src/effects/ScienFilter.h
+++ b/src/effects/ScienFilter.h
@@ -15,7 +15,6 @@ Vaughan Johnson (Preview)
 
 #include <wx/setup.h> // for wxUSE_* macros
 
-#include <wx/arrstr.h>
 #include <wx/bitmap.h>
 #include <wx/choice.h>
 #include <wx/event.h>
diff --git a/src/effects/ToneGen.h b/src/effects/ToneGen.h
index c3ac7eead..d57852eca 100644
--- a/src/effects/ToneGen.h
+++ b/src/effects/ToneGen.h
@@ -13,8 +13,6 @@
 #ifndef __AUDACITY_EFFECT_TONEGEN__
 #define __AUDACITY_EFFECT_TONEGEN__
 
-#include <wx/arrstr.h>
-
 #include "../widgets/NumericTextCtrl.h"
 
 #include "Effect.h"
diff --git a/src/effects/TruncSilence.h b/src/effects/TruncSilence.h
index 6a155f3bb..46fa2f788 100644
--- a/src/effects/TruncSilence.h
+++ b/src/effects/TruncSilence.h
@@ -17,7 +17,6 @@
 #ifndef __AUDACITY_EFFECT_TRUNC_SILENCE__
 #define __AUDACITY_EFFECT_TRUNC_SILENCE__
 
-#include <wx/arrstr.h>
 #include <wx/event.h>
 #include <wx/list.h>
 
diff --git a/src/effects/lv2/LV2Effect.h b/src/effects/lv2/LV2Effect.h
index bebdbaa63..5f4145ac4 100644
--- a/src/effects/lv2/LV2Effect.h
+++ b/src/effects/lv2/LV2Effect.h
@@ -13,6 +13,8 @@
 
 #if USE_LV2
 
+class wxArrayString;
+
 #include "../../MemoryX.h"
 #include <vector>
 #include <wx/checkbox.h>
diff --git a/src/effects/nyquist/Nyquist.h b/src/effects/nyquist/Nyquist.h
index 5508610ff..7f46a090b 100644
--- a/src/effects/nyquist/Nyquist.h
+++ b/src/effects/nyquist/Nyquist.h
@@ -27,6 +27,8 @@
 
 #include "nyx.h"
 
+class wxArrayString;
+
 #define NYQUISTEFFECTS_VERSION wxT("1.0.0.0")
 /* i18n-hint: "Nyquist" is an embedded interpreted programming language in
  Audacity, named in honor of the Swedish-American Harry Nyquist (or Nyqvist).
diff --git a/src/export/Export.h b/src/export/Export.h
index fd8288e4d..685d82b13 100644
--- a/src/export/Export.h
+++ b/src/export/Export.h
@@ -20,6 +20,7 @@
 #include "../SampleFormat.h"
 #include "../widgets/wxPanelWrapper.h"
 
+class wxArrayString;
 class FileDialogWrapper;
 class wxFileCtrlEvent;
 class wxMemoryDC;
diff --git a/src/export/ExportFFmpegDialogs.h b/src/export/ExportFFmpegDialogs.h
index 680c4275e..7de358339 100644
--- a/src/export/ExportFFmpegDialogs.h
+++ b/src/export/ExportFFmpegDialogs.h
@@ -27,6 +27,8 @@ LRN
 
 class wxArrayStringEx;
 
+class wxArrayString;
+
 /// Identifiers for pre-set export types.
 enum FFmpegExposedFormat
 {
diff --git a/src/import/Import.h b/src/import/Import.h
index fab38df0f..697c648c8 100644
--- a/src/import/Import.h
+++ b/src/import/Import.h
@@ -15,12 +15,12 @@
 #include "ImportForwards.h"
 #include "audacity/Types.h"
 #include <vector>
-#include <wx/arrstr.h>
 #include <wx/listbox.h>
 #include <wx/tokenzr.h>
 
 #include "../widgets/wxPanelWrapper.h"
 
+class wxArrayString;
 class Tags;
 class TrackFactory;
 class Track;
diff --git a/src/import/ImportPlugin.h b/src/import/ImportPlugin.h
index 08b3470ab..39c1fc5ef 100644
--- a/src/import/ImportPlugin.h
+++ b/src/import/ImportPlugin.h
@@ -66,6 +66,7 @@ but little else.
 
 #include "ImportRaw.h" // defines TrackHolders
 
+class wxArrayString;
 class TrackFactory;
 class Track;
 class Tags;
diff --git a/src/ondemand/ODDecodeFlacTask.h b/src/ondemand/ODDecodeFlacTask.h
index 3293bfe48..7e8dbe18b 100644
--- a/src/ondemand/ODDecodeFlacTask.h
+++ b/src/ondemand/ODDecodeFlacTask.h
@@ -34,6 +34,7 @@ robust enough to allow all the user changes such as copy/paste, DELETE, and so o
 
 #include "FLAC++/decoder.h"
 
+class wxArrayString;
 class ODDecodeBlockFile;
 class WaveTrack;
 class ODFileDecoder;
diff --git a/src/prefs/EffectsPrefs.h b/src/prefs/EffectsPrefs.h
index 62a14156c..0d891d021 100644
--- a/src/prefs/EffectsPrefs.h
+++ b/src/prefs/EffectsPrefs.h
@@ -15,7 +15,6 @@
 
 #include <wx/defs.h>
 
-#include <wx/arrstr.h>
 #include <wx/window.h>
 
 #include "PrefsPanel.h"
diff --git a/src/prefs/GUIPrefs.h b/src/prefs/GUIPrefs.h
index b10e9ccd4..43ac7ebb6 100644
--- a/src/prefs/GUIPrefs.h
+++ b/src/prefs/GUIPrefs.h
@@ -15,7 +15,6 @@
 
 #include <wx/defs.h>
 
-#include <wx/arrstr.h>
 #include <wx/window.h>
 
 #include "PrefsPanel.h"
diff --git a/src/prefs/ModulePrefs.h b/src/prefs/ModulePrefs.h
index d4a6265f6..9b487833f 100644
--- a/src/prefs/ModulePrefs.h
+++ b/src/prefs/ModulePrefs.h
@@ -20,6 +20,7 @@
 #include "PrefsPanel.h"
 
 
+class wxArrayString;
 class ShuttleGui;
 
 enum {
diff --git a/src/prefs/QualityPrefs.h b/src/prefs/QualityPrefs.h
index f48461b55..6568f948d 100644
--- a/src/prefs/QualityPrefs.h
+++ b/src/prefs/QualityPrefs.h
@@ -15,7 +15,6 @@
 #include <vector>
 #include <wx/defs.h>
 
-#include <wx/arrstr.h>
 #include <wx/choice.h>
 #include <wx/textctrl.h>
 
diff --git a/src/prefs/SpectrogramSettings.h b/src/prefs/SpectrogramSettings.h
index f60c2bbf5..662c52a5f 100644
--- a/src/prefs/SpectrogramSettings.h
+++ b/src/prefs/SpectrogramSettings.h
@@ -21,7 +21,6 @@ Paul Licameli
 struct FFTParam;
 class NumberScale;
 class SpectrumPrefs;
-class wxArrayString;
 class wxArrayStringEx;
 
 class SpectrogramSettings
diff --git a/src/prefs/SpectrumPrefs.h b/src/prefs/SpectrumPrefs.h
index 020cc3093..25a711120 100644
--- a/src/prefs/SpectrumPrefs.h
+++ b/src/prefs/SpectrumPrefs.h
@@ -32,7 +32,6 @@
 #include "SpectrogramSettings.h"
 
 class wxArrayStringEx;
-
 class wxChoice;
 class wxCheckBox;
 class wxTextCtrl;
diff --git a/src/prefs/TracksPrefs.h b/src/prefs/TracksPrefs.h
index 2777e22ad..3e4c1ee41 100644
--- a/src/prefs/TracksPrefs.h
+++ b/src/prefs/TracksPrefs.h
@@ -15,7 +15,6 @@
 
 //#include <wx/defs.h>
 
-//#include <wx/arrstr.h>
 //#include <wx/window.h>
 
 #include <vector>
diff --git a/src/widgets/ASlider.cpp b/src/widgets/ASlider.cpp
index 85455dd9f..6a0019943 100644
--- a/src/widgets/ASlider.cpp
+++ b/src/widgets/ASlider.cpp
@@ -77,6 +77,8 @@ const int sliderFontSize = 12;
 #define OPTIONAL_SLIDER_TICKS
 #endif
 
+class wxArrayString;
+
 //
 // TipPanel
 //
diff --git a/src/widgets/ASlider.h b/src/widgets/ASlider.h
index 8d8b9450d..8ff085c77 100644
--- a/src/widgets/ASlider.h
+++ b/src/widgets/ASlider.h
@@ -26,6 +26,7 @@
 #include "WindowAccessible.h"
 #endif
 
+class wxArrayString;
 class wxBitmap;
 class wxCursor;
 class wxImage;
diff --git a/src/widgets/Grid.h b/src/widgets/Grid.h
index 60b04ad4e..395cbaefa 100644
--- a/src/widgets/Grid.h
+++ b/src/widgets/Grid.h
@@ -30,6 +30,7 @@ class GridAx;
 
 #endif
 
+class wxArrayString;
 class NumericTextCtrl;
 
 /**********************************************************************//**
diff --git a/src/widgets/KeyView.h b/src/widgets/KeyView.h
index bb0ba7de2..0f62dbbe8 100644
--- a/src/widgets/KeyView.h
+++ b/src/widgets/KeyView.h
@@ -15,11 +15,12 @@
 #include <vector>
 #include <wx/setup.h> // for wxUSE_* macros
 #include <wx/defs.h>
-#include <wx/arrstr.h>
 #include <wx/vlbox.h>
 
 #include "../commands/Keyboard.h"
 
+class wxArrayString;
+
 // Class holding all information about a node.  Rather than a real tree
 // we store these in an array and simulate a tree.
 class KeyNode
diff --git a/src/wxFileNameWrapper.h b/src/wxFileNameWrapper.h
index ffaaeae2a..06848731b 100644
--- a/src/wxFileNameWrapper.h
+++ b/src/wxFileNameWrapper.h
@@ -11,6 +11,8 @@ Paul Licameli
 #ifndef __AUDACITY_WXFILENAMEWRAPPER__
 #define __AUDACITY_WXFILENAMEWRAPPER__
 
+class wxArrayString;
+
 // The wxFileName does not have a move constructor.
 // So add one to it, so that it passes around by value more quickly.
 class wxFileNameWrapper : public wxFileName
diff --git a/src/xml/XMLWriter.h b/src/xml/XMLWriter.h
index 8180c0bb4..ad9056d27 100644
--- a/src/xml/XMLWriter.h
+++ b/src/xml/XMLWriter.h
@@ -11,7 +11,6 @@
 #define __AUDACITY_XML_XML_FILE_WRITER__
 
 #include <vector>
-#include <wx/arrstr.h>
 #include <wx/ffile.h>
 
 #include "../FileException.h"