diff --git a/dlls/quartz/videorenderer.c b/dlls/quartz/videorenderer.c
index 87491d8851c..a16a422e2d5 100644
--- a/dlls/quartz/videorenderer.c
+++ b/dlls/quartz/videorenderer.c
@@ -53,6 +53,8 @@ typedef struct VideoRendererImpl
     LONG VideoWidth;
     LONG VideoHeight;
     LONG FullScreenMode;
+
+    DWORD saved_style;
 } VideoRendererImpl;
 
 static inline VideoRendererImpl *impl_from_BaseWindow(BaseWindow *iface)
@@ -392,17 +394,6 @@ static void video_renderer_start_stream(BaseRenderer *iface)
     }
 }
 
-static LPWSTR WINAPI VideoRenderer_GetClassWindowStyles(BaseWindow *This, DWORD *pClassStyles, DWORD *pWindowStyles, DWORD *pWindowStylesEx)
-{
-    static const WCHAR classnameW[] = { 'W','i','n','e',' ','A','c','t','i','v','e','M','o','v','i','e',' ','C','l','a','s','s',0 };
-
-    *pClassStyles = 0;
-    *pWindowStyles = WS_SIZEBOX;
-    *pWindowStylesEx = 0;
-
-    return (LPWSTR)classnameW;
-}
-
 static RECT WINAPI VideoRenderer_GetDefaultRect(BaseWindow *iface)
 {
     VideoRendererImpl *This = impl_from_BaseWindow(iface);
@@ -441,7 +432,6 @@ static const BaseRendererFuncTable BaseFuncTable =
 };
 
 static const BaseWindowFuncTable renderer_BaseWindowFuncTable = {
-    VideoRenderer_GetClassWindowStyles,
     VideoRenderer_GetDefaultRect,
     VideoRenderer_OnSize
 };
@@ -674,7 +664,7 @@ static HRESULT WINAPI VideoWindow_put_FullScreenMode(IVideoWindow *iface,
     FIXME("(%p/%p)->(%d): stub !!!\n", This, iface, FullScreenMode);
 
     if (FullScreenMode) {
-        This->baseControlWindow.baseWindow.WindowStyles = GetWindowLongW(This->baseControlWindow.baseWindow.hWnd, GWL_STYLE);
+        This->saved_style = GetWindowLongW(This->baseControlWindow.baseWindow.hWnd, GWL_STYLE);
         ShowWindow(This->baseControlWindow.baseWindow.hWnd, SW_HIDE);
         SetParent(This->baseControlWindow.baseWindow.hWnd, 0);
         SetWindowLongW(This->baseControlWindow.baseWindow.hWnd, GWL_STYLE, WS_POPUP);
@@ -684,7 +674,7 @@ static HRESULT WINAPI VideoWindow_put_FullScreenMode(IVideoWindow *iface,
     } else {
         ShowWindow(This->baseControlWindow.baseWindow.hWnd, SW_HIDE);
         SetParent(This->baseControlWindow.baseWindow.hWnd, This->baseControlWindow.hwndOwner);
-        SetWindowLongW(This->baseControlWindow.baseWindow.hWnd, GWL_STYLE, This->baseControlWindow.baseWindow.WindowStyles);
+        SetWindowLongW(This->baseControlWindow.baseWindow.hWnd, GWL_STYLE, This->saved_style);
         GetClientRect(This->baseControlWindow.baseWindow.hWnd, &This->DestRect);
         SetWindowPos(This->baseControlWindow.baseWindow.hWnd,0,This->DestRect.left,This->DestRect.top,This->DestRect.right,This->DestRect.bottom,SWP_NOZORDER|SWP_SHOWWINDOW);
         This->WindowPos = This->DestRect;
diff --git a/dlls/quartz/vmr9.c b/dlls/quartz/vmr9.c
index d3fdfb13a39..536703fbff1 100644
--- a/dlls/quartz/vmr9.c
+++ b/dlls/quartz/vmr9.c
@@ -568,17 +568,6 @@ static const BaseRendererFuncTable BaseFuncTable =
     .renderer_pin_query_interface = vmr_pin_query_interface,
 };
 
-static LPWSTR WINAPI VMR9_GetClassWindowStyles(BaseWindow *This, DWORD *pClassStyles, DWORD *pWindowStyles, DWORD *pWindowStylesEx)
-{
-    static WCHAR classnameW[] = { 'I','V','M','R','9',' ','C','l','a','s','s', 0 };
-
-    *pClassStyles = 0;
-    *pWindowStyles = WS_SIZEBOX;
-    *pWindowStylesEx = 0;
-
-    return classnameW;
-}
-
 static RECT WINAPI VMR9_GetDefaultRect(BaseWindow *This)
 {
     struct quartz_vmr* pVMR9 = impl_from_BaseWindow(This);
@@ -604,7 +593,6 @@ static BOOL WINAPI VMR9_OnSize(BaseWindow *This, LONG Width, LONG Height)
 }
 
 static const BaseWindowFuncTable renderer_BaseWindowFuncTable = {
-    VMR9_GetClassWindowStyles,
     VMR9_GetDefaultRect,
     VMR9_OnSize,
 };
diff --git a/dlls/strmbase/window.c b/dlls/strmbase/window.c
index fbf0edc78c5..142336bc193 100644
--- a/dlls/strmbase/window.c
+++ b/dlls/strmbase/window.c
@@ -110,33 +110,24 @@ HRESULT WINAPI BaseWindow_Destroy(BaseWindow *This)
 
 HRESULT WINAPI BaseWindowImpl_PrepareWindow(BaseWindow *This)
 {
-    WNDCLASSW winclass;
+    static const WCHAR class_nameW[] = {'w','i','n','e','_','s','t','r','m','b','a','s','e','_','w','i','n','d','o','w',0};
     static const WCHAR windownameW[] = { 'A','c','t','i','v','e','M','o','v','i','e',' ','W','i','n','d','o','w',0 };
+    WNDCLASSW winclass = {0};
 
-    This->pClassName = This->pFuncsTable->pfnGetClassWindowStyles(This, &This->ClassStyles, &This->WindowStyles, &This->WindowStylesEx);
-
-    winclass.style = This->ClassStyles;
     winclass.lpfnWndProc = WndProcW;
-    winclass.cbClsExtra = 0;
     winclass.cbWndExtra = sizeof(BaseWindow*);
     winclass.hInstance = This->hInstance;
-    winclass.hIcon = NULL;
-    winclass.hCursor = NULL;
     winclass.hbrBackground = GetStockObject(BLACK_BRUSH);
-    winclass.lpszMenuName = NULL;
-    winclass.lpszClassName = This->pClassName;
+    winclass.lpszClassName = class_nameW;
     if (!RegisterClassW(&winclass) && GetLastError() != ERROR_CLASS_ALREADY_EXISTS)
     {
         ERR("Unable to register window class: %u\n", GetLastError());
         return E_FAIL;
     }
 
-    This->hWnd = CreateWindowExW(This->WindowStylesEx,
-                                 This->pClassName, windownameW,
-                                 This->WindowStyles,
-                                 CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
-                                 CW_USEDEFAULT, NULL, NULL, This->hInstance,
-                                 NULL);
+    This->hWnd = CreateWindowExW(0, class_nameW, windownameW, WS_SIZEBOX,
+            CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
+            NULL, NULL, This->hInstance, NULL);
 
     if (!This->hWnd)
     {
@@ -305,7 +296,6 @@ HRESULT WINAPI BaseControlWindowImpl_put_WindowStyle(IVideoWindow *iface, LONG W
     SetWindowLongW(This->baseWindow.hWnd, GWL_STYLE, WindowStyle);
     SetWindowPos(This->baseWindow.hWnd, 0, 0, 0, 0, 0,
             SWP_NOSIZE | SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
-    This->baseWindow.WindowStyles = WindowStyle;
 
     return S_OK;
 }
diff --git a/include/wine/strmbase.h b/include/wine/strmbase.h
index 34a558ab8e8..11397170edc 100644
--- a/include/wine/strmbase.h
+++ b/include/wine/strmbase.h
@@ -360,23 +360,17 @@ typedef struct tagBaseWindow
 	LONG Width;
 	LONG Height;
 	HINSTANCE hInstance;
-	LPWSTR pClassName;
-	DWORD ClassStyles;
-	DWORD WindowStyles;
-	DWORD WindowStylesEx;
 	HDC hDC;
 
 	const struct BaseWindowFuncTable* pFuncsTable;
 } BaseWindow;
 
-typedef LPWSTR (WINAPI *BaseWindow_GetClassWindowStyles)(BaseWindow *This, DWORD *pClassStyles, DWORD *pWindowStyles, DWORD *pWindowStylesEx);
 typedef RECT (WINAPI *BaseWindow_GetDefaultRect)(BaseWindow *This);
 typedef BOOL (WINAPI *BaseWindow_OnSize)(BaseWindow *This, LONG Height, LONG Width);
 
 typedef struct BaseWindowFuncTable
 {
 	/* Required */
-	BaseWindow_GetClassWindowStyles pfnGetClassWindowStyles;
 	BaseWindow_GetDefaultRect pfnGetDefaultRect;
 	/* Optional, WinProc Related */
 	BaseWindow_OnSize pfnOnSize;