unreleased regression - attendee report generates undefined property notice
You can replicate this on dmaster demo by clicking "Refresh Results" on the "Attendee List" report. You'll get this notice once per contact:
Notice: Undefined property: CRM_Report_Form_Event_ParticipantListing::$campaigns in CRM_Report_Form_Event_ParticipantListing->alterDisplay() (line 748 of /srv/buildkit/build/dmaster/sites/all/modules/civicrm/CRM/Report/Form/Event/ParticipantListing.php).
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