This is an addon module for EditableSign (a free plugin). This addon adds functions to specify nominated keywords to indicate untouchable (non-editable sign).  If a sign contains any of keywords listed in the Untouchable_config.yml, EditableSign won't allow you to edit the sign unless you have "editablesign.bypass.untouchable" permission node.

Installation:
Place Untouchable-x.x.x.jar file in plugin/EditableSign/addons folder, and restart your server.

Configuration:

EditableSign:
  Untouchable:
    cannot_edit_message: "&c[ES] You cannot edit this sign!"
    untouchables:
      - "(?i)\\[buy\\]"
      - "(?i)\\[sell\\]"