When applying or okaying IDLE configuration (Options-> Configure IDLE) all text in the shell window loses highlighting. Text in the shell window created after the configuration is applied is highlighted though.
Attached is a patch to fix this issue. The ModifiedColorDelegator already marks everything before "iomark" as SYNC'ed. This is good, as the ColorDelegator should not be trying to colorize STDOUT text as Python code. Resetting the ColorDelegator in _rmcolorizer in EditorWindow.py calls .removecolors(). The patch modifies this method to only remove tags *after* the iomark.
title: When changing IDLE configuration all text in editor window loses highlighting -> When changing IDLE configuration all text in shell window loses highlighting