Remove action(s) from the action list which match {string}.   The
'*' character will act as a wildcard and will match any text.
See help wildcard.
examples:
#unaction {%0tells you%1}
remove the action that is triggered by '%0tells you%1'
#unaction *
remove all actions
#unaction {*massacre*}
remove all actions that contain the word 'massacre'