This message enables screen refreshes. This allows an application to make changes throughout a document while avoiding unnecessary overhead caused by attempts to keep the screen display current. When an MLM_ENABLEREFRESH message is sent, the screen display is brought up to date with the contents of the text.
While refresh is disabled, mouse and keyboard messages are processed by beeping and ignoring them, except for mouse moves, which do not beep; the mouse pointer changes to the system standard wait symbol (a clock face).