change_receiver: removed redundant Swing_Thread wrapper -- the Delay timer action is already in Swing; added update_delay, which invokes token markup via buffer.propertiesChanged (potentially many other things?);
change_receiver: removed redundant Swing_Thread wrapper -- the Delay timer action is already in Swing;
added update_delay, which invokes token markup via buffer.propertiesChanged (potentially many other things?);

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