Short: TextEditor custom class for MUI
Version: 15.51
Url: http://aminet.net/dev/mui/MCC_TextEditor-15.51.lha

MCC_TextEditor/Developer/Autodocs/MCC/MCC_TextEditor.doc
MCC_TextEditor/Developer/C/include/mui/TextEditor_mcc.h
MCC_TextEditor/Docs/MCC_TextEditor.guide