WM_CANCELMODE top-level constant Null safety
Sent to cancel certain modes, such as mouse capture. For example, the system sends this message to the active window when a dialog box or message box is displayed. Certain functions also send this message explicitly to the specified window regardless of whether it is the active window. For example, the EnableWindow function sends this message when disabling the specified window.
const WM_CANCELMODE = 0x001F;