diff --git a/src/applications/herald/controller/HeraldTranscriptController.php b/src/applications/herald/controller/HeraldTranscriptController.php
--- a/src/applications/herald/controller/HeraldTranscriptController.php
+++ b/src/applications/herald/controller/HeraldTranscriptController.php
@@ -761,6 +761,11 @@
   private function getTranscriptTransactionPHIDs(HeraldTranscript $xscript) {
 
     $object_xscript = $xscript->getObjectTranscript();
+    // Work around https://we.phorge.it/T15343: For unknown reasons, calling
+    // getObjectTranscript() on $xscript returns a "false" boolean sometimes.
+    if ($object_xscript === false) {
+      return array();
+    }
     $xaction_phids = $object_xscript->getAppliedTransactionPHIDs();
 
     // If the value is "null", this is an older transcript or this adapter