fix #12963

(cherry picked from commit 6b048f59d74e67189965edd783574bb1a98d4ba4)

src/video/windows/SDL_windowsevents.c

@@ -1431,8 +1431,6 @@ LRESULT CALLBACK WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPara
             }
         }
         
-        return 0;
-        
     } break;
 
     case WM_LBUTTONUP: