GitHub labels appear to prefer short-hand syntax over literal emojis

.github/stale.yml

@@ -18,7 +18,7 @@ exemptLabels:
   - 'Triage 🏳️'
   - 'Announcement 🎉'
 # Label to use when marking an issue as stale
-staleLabel: 'Stale 🥖'
+staleLabel: 'Stale :baguette_bread:'
 # Comment to post when marking an issue as stale. Set to `false` to disable
 markComment: >
   This issue has been automatically marked as stale because it has not had