diff --git a/fxbarcode/BC_Library.h b/fxbarcode/BC_Library.h
index af38a81..5f1af4d 100644
--- a/fxbarcode/BC_Library.h
+++ b/fxbarcode/BC_Library.h
@@ -7,7 +7,9 @@
 #ifndef FXBARCODE_BC_LIBRARY_H_
 #define FXBARCODE_BC_LIBRARY_H_
 
-enum BC_TEXT_LOC {
+#include <stdint.h>
+
+enum BC_TEXT_LOC : uint8_t {
   BC_TEXT_LOC_NONE = 0,
   BC_TEXT_LOC_ABOVE,
   BC_TEXT_LOC_BELOW,
@@ -15,9 +17,12 @@
   BC_TEXT_LOC_BELOWEMBED
 };
 
-enum BC_CHAR_ENCODING { CHAR_ENCODING_UTF8 = 0, CHAR_ENCODING_UNICODE };
+enum BC_CHAR_ENCODING : uint8_t {
+  CHAR_ENCODING_UTF8 = 0,
+  CHAR_ENCODING_UNICODE
+};
 
-enum BC_TYPE {
+enum BC_TYPE : int8_t {
   BC_UNKNOWN = -1,
   BC_CODE39 = 0,
   BC_CODABAR,
diff --git a/xfa/fwl/cfwl_barcode.h b/xfa/fwl/cfwl_barcode.h
index 64a21d3..d2cd716 100644
--- a/xfa/fwl/cfwl_barcode.h
+++ b/xfa/fwl/cfwl_barcode.h
@@ -69,21 +69,21 @@
   void GenerateBarcodeImageCache();
   void CreateBarcodeEngine();
 
-  std::unique_ptr<CFX_Barcode> m_pBarcodeEngine;
-  Status m_eStatus = Status::kNormal;
   BC_TYPE m_type = BC_UNKNOWN;
-  BC_CHAR_ENCODING m_eCharEncoding;
-  int32_t m_nModuleHeight;
-  int32_t m_nModuleWidth;
-  int32_t m_nDataLength;
-  bool m_bCalChecksum;
-  bool m_bPrintChecksum;
-  BC_TEXT_LOC m_eTextLocation;
-  int8_t m_nWideNarrowRatio;
-  char m_cStartChar;
-  char m_cEndChar;
-  int32_t m_nECLevel;
+  BC_CHAR_ENCODING m_eCharEncoding = CHAR_ENCODING_UTF8;
+  BC_TEXT_LOC m_eTextLocation = BC_TEXT_LOC_NONE;
+  Status m_eStatus = Status::kNormal;
+  bool m_bCalChecksum = false;
+  bool m_bPrintChecksum = false;
+  char m_cStartChar = 0;
+  char m_cEndChar = 0;
+  int8_t m_nWideNarrowRatio = 1;
+  int32_t m_nModuleHeight = -1;
+  int32_t m_nModuleWidth = -1;
+  int32_t m_nDataLength = 0;
+  int32_t m_nECLevel = 0;
   uint32_t m_dwAttributeMask = 0;
+  std::unique_ptr<CFX_Barcode> m_pBarcodeEngine;
 };
 
 #endif  // XFA_FWL_CFWL_BARCODE_H_
diff --git a/xfa/fwl/cfwl_combolist.cpp b/xfa/fwl/cfwl_combolist.cpp
index 7c30bdf..d25f312 100644
--- a/xfa/fwl/cfwl_combolist.cpp
+++ b/xfa/fwl/cfwl_combolist.cpp
@@ -21,7 +21,7 @@
     const CFWL_App* app,
     std::unique_ptr<CFWL_WidgetProperties> properties,
     CFWL_Widget* pOuter)
-    : CFWL_ListBox(app, std::move(properties), pOuter), m_bNotifyOwner(true) {
+    : CFWL_ListBox(app, std::move(properties), pOuter) {
   ASSERT(pOuter);
 }
 
diff --git a/xfa/fwl/cfwl_combolist.h b/xfa/fwl/cfwl_combolist.h
index 24a1012..c275c72 100644
--- a/xfa/fwl/cfwl_combolist.h
+++ b/xfa/fwl/cfwl_combolist.h
@@ -35,7 +35,7 @@
   bool OnDropListKey(CFWL_MessageKey* pKey);
   void OnDropListKeyDown(CFWL_MessageKey* pKey);
 
-  bool m_bNotifyOwner;
+  bool m_bNotifyOwner = true;
 };
 
 #endif  // XFA_FWL_CFWL_COMBOLIST_H_
diff --git a/xfa/fwl/cfwl_eventmouse.h b/xfa/fwl/cfwl_eventmouse.h
index 273856f..e7982fb 100644
--- a/xfa/fwl/cfwl_eventmouse.h
+++ b/xfa/fwl/cfwl_eventmouse.h
@@ -16,7 +16,7 @@
   CFWL_EventMouse(CFWL_Widget* pSrcTarget, CFWL_Widget* pDstTarget);
   ~CFWL_EventMouse() override;
 
-  FWL_MouseCommand m_dwCmd;
+  FWL_MouseCommand m_dwCmd = FWL_MouseCommand::LeftButtonDown;
 };
 
 #endif  // XFA_FWL_CFWL_EVENTMOUSE_H_
diff --git a/xfa/fwl/cfwl_eventscroll.h b/xfa/fwl/cfwl_eventscroll.h
index 0491ad7..78960c8 100644
--- a/xfa/fwl/cfwl_eventscroll.h
+++ b/xfa/fwl/cfwl_eventscroll.h
@@ -27,8 +27,8 @@
   explicit CFWL_EventScroll(CFWL_Widget* pSrcTarget);
   ~CFWL_EventScroll() override;
 
-  Code m_iScrollCode;
-  float m_fPos;
+  Code m_iScrollCode = Code::None;
+  float m_fPos = 0.0f;
 };
 
 #endif  // XFA_FWL_CFWL_EVENTSCROLL_H_
diff --git a/xfa/fwl/cfwl_eventselectchanged.h b/xfa/fwl/cfwl_eventselectchanged.h
index 176cb87..d4b68b3 100644
--- a/xfa/fwl/cfwl_eventselectchanged.h
+++ b/xfa/fwl/cfwl_eventselectchanged.h
@@ -15,12 +15,12 @@
   ~CFWL_EventSelectChanged() override;
 
   // Used by ComboBox.
-  bool bLButtonUp;
+  bool bLButtonUp = false;
 
   // Used by DateTimePIcker
-  int32_t iYear;
-  int32_t iMonth;
-  int32_t iDay;
+  int32_t iYear = -1;
+  int32_t iMonth = -1;
+  int32_t iDay = -1;
 };
 
 #endif  // XFA_FWL_CFWL_EVENTSELECTCHANGED_H_
diff --git a/xfa/fwl/cfwl_eventtarget.cpp b/xfa/fwl/cfwl_eventtarget.cpp
index d6a717d..4b3d87c 100644
--- a/xfa/fwl/cfwl_eventtarget.cpp
+++ b/xfa/fwl/cfwl_eventtarget.cpp
@@ -10,7 +10,7 @@
 #include "xfa/fwl/ifwl_widgetdelegate.h"
 
 CFWL_EventTarget::CFWL_EventTarget(CFWL_Widget* pListener)
-    : m_pListener(pListener), m_bValid(true) {}
+    : m_pListener(pListener) {}
 
 CFWL_EventTarget::~CFWL_EventTarget() {}
 
diff --git a/xfa/fwl/cfwl_eventtarget.h b/xfa/fwl/cfwl_eventtarget.h
index b5a8bdb..f614319 100644
--- a/xfa/fwl/cfwl_eventtarget.h
+++ b/xfa/fwl/cfwl_eventtarget.h
@@ -26,9 +26,9 @@
   void FlagInvalid() { m_bValid = false; }
 
  private:
+  bool m_bValid = true;
+  CFWL_Widget* const m_pListener;
   std::set<CFWL_Widget*> m_widgets;
-  CFWL_Widget* m_pListener;
-  bool m_bValid;
 };
 
 #endif  // XFA_FWL_CFWL_EVENTTARGET_H_
diff --git a/xfa/fwl/cfwl_eventvalidate.h b/xfa/fwl/cfwl_eventvalidate.h
index 7d88b97..26e3c7f 100644
--- a/xfa/fwl/cfwl_eventvalidate.h
+++ b/xfa/fwl/cfwl_eventvalidate.h
@@ -14,8 +14,8 @@
   explicit CFWL_EventValidate(CFWL_Widget* pSrcTarget);
   ~CFWL_EventValidate() override;
 
+  bool bValidate = false;
   WideString wsInsert;
-  bool bValidate;
 };
 
 #endif  // XFA_FWL_CFWL_EVENTVALIDATE_H_
diff --git a/xfa/fwl/cfwl_messagekey.h b/xfa/fwl/cfwl_messagekey.h
index 3b46531..b122647 100644
--- a/xfa/fwl/cfwl_messagekey.h
+++ b/xfa/fwl/cfwl_messagekey.h
@@ -21,9 +21,9 @@
                   uint32_t keycode);
   ~CFWL_MessageKey() override;
 
-  FWL_KeyCommand m_dwCmd;
-  uint32_t m_dwFlags;
-  uint32_t m_dwKeyCode;
+  const FWL_KeyCommand m_dwCmd;
+  const uint32_t m_dwFlags;
+  const uint32_t m_dwKeyCode;
 };
 
 #endif  // XFA_FWL_CFWL_MESSAGEKEY_H_
diff --git a/xfa/fwl/cfwl_messagemouse.h b/xfa/fwl/cfwl_messagemouse.h
index b0cea2a..10c298a 100644
--- a/xfa/fwl/cfwl_messagemouse.h
+++ b/xfa/fwl/cfwl_messagemouse.h
@@ -34,7 +34,7 @@
                     CFX_PointF pos);
   ~CFWL_MessageMouse() override;
 
-  FWL_MouseCommand m_dwCmd;
+  const FWL_MouseCommand m_dwCmd;
   uint32_t m_dwFlags = 0;
   CFX_PointF m_pos;
 };
diff --git a/xfa/fwl/cfwl_messagemousewheel.h b/xfa/fwl/cfwl_messagemousewheel.h
index 8eb4be7..9908951 100644
--- a/xfa/fwl/cfwl_messagemousewheel.h
+++ b/xfa/fwl/cfwl_messagemousewheel.h
@@ -20,7 +20,7 @@
                          CFX_PointF delta);
   ~CFWL_MessageMouseWheel() override;
 
-  uint32_t m_dwFlags;
+  const uint32_t m_dwFlags;
   CFX_PointF m_pos;
   CFX_PointF m_delta;
 };
diff --git a/xfa/fwl/cfwl_pushbutton.cpp b/xfa/fwl/cfwl_pushbutton.cpp
index 980a89d..7806399 100644
--- a/xfa/fwl/cfwl_pushbutton.cpp
+++ b/xfa/fwl/cfwl_pushbutton.cpp
@@ -22,8 +22,7 @@
 #include "xfa/fwl/ifwl_themeprovider.h"
 
 CFWL_PushButton::CFWL_PushButton(const CFWL_App* app)
-    : CFWL_Widget(app, pdfium::MakeUnique<CFWL_WidgetProperties>(), nullptr),
-      m_bBtnDown(false) {}
+    : CFWL_Widget(app, pdfium::MakeUnique<CFWL_WidgetProperties>(), nullptr) {}
 
 CFWL_PushButton::~CFWL_PushButton() {}
 
diff --git a/xfa/fwl/cfwl_pushbutton.h b/xfa/fwl/cfwl_pushbutton.h
index 7c68017..925dbb6 100644
--- a/xfa/fwl/cfwl_pushbutton.h
+++ b/xfa/fwl/cfwl_pushbutton.h
@@ -44,9 +44,9 @@
   void OnMouseLeave(CFWL_MessageMouse* pMsg);
   void OnKeyDown(CFWL_MessageKey* pMsg);
 
+  bool m_bBtnDown = false;
   CFX_RectF m_rtClient;
   CFX_RectF m_rtCaption;
-  bool m_bBtnDown;
 };
 
 #endif  // XFA_FWL_CFWL_PUSHBUTTON_H_
diff --git a/xfa/fwl/cfwl_themetext.h b/xfa/fwl/cfwl_themetext.h
index a63b8bf..f0cfaa7 100644
--- a/xfa/fwl/cfwl_themetext.h
+++ b/xfa/fwl/cfwl_themetext.h
@@ -13,12 +13,12 @@
 
 class CFWL_ThemeText final : public CFWL_ThemePart {
  public:
-  CFWL_ThemeText() : m_pGraphics(nullptr) {}
+  CFWL_ThemeText() = default;
 
+  FDE_TextAlignment m_iTTOAlign = FDE_TextAlignment::kTopLeft;
+  CXFA_Graphics* m_pGraphics = nullptr;
   WideString m_wsText;
   FDE_TextStyle m_dwTTOStyles;
-  FDE_TextAlignment m_iTTOAlign;
-  CXFA_Graphics* m_pGraphics;
 };
 
 #endif  // XFA_FWL_CFWL_THEMETEXT_H_
diff --git a/xfa/fwl/cfwl_widgetproperties.h b/xfa/fwl/cfwl_widgetproperties.h
index 5e9cf24..4148833 100644
--- a/xfa/fwl/cfwl_widgetproperties.h
+++ b/xfa/fwl/cfwl_widgetproperties.h
@@ -20,10 +20,10 @@
   CFWL_WidgetProperties();
   ~CFWL_WidgetProperties();
 
-  CFX_RectF m_rtWidget;
   uint32_t m_dwStyles = FWL_WGTSTYLE_Child;
   uint32_t m_dwStyleExes = 0;
   uint32_t m_dwStates = 0;
+  CFX_RectF m_rtWidget;
   UnownedPtr<IFWL_ThemeProvider> m_pThemeProvider;
   CFWL_Widget* m_pParent = nullptr;  // Raw, this class owned by node in tree.
 };