diff --git a/public/js/modules/editor.js b/public/js/modules/editor.js
index 8b7cf8f..bd7ebb4 100644
--- a/public/js/modules/editor.js
+++ b/public/js/modules/editor.js
@@ -231,7 +231,10 @@ export function openModal(card = null) {
     // bucket — they belong to a calendar, not a kanban column. For
     // every other new card, inherit the active real bucket if we're
     // in one so the user doesn't have to re-pick it.
-    const isNewAppointment = !card && /#(termin|geburtstag)\b/.test(body.value);
+    // `card` can be `null` (add-button new) or a shell `{id: null, ...}`
+    // from the calendar day-popup — both count as "new", so key on
+    // card?.id not the card ref itself.
+    const isNewAppointment = !card?.id && /#(termin|geburtstag)\b/.test(body.value);
     inpBucket.value = card?.bucket_id ? card.bucket_id
         : (isNewAppointment ? ''
            : (!virtualBuckets.includes(state.activeBucket) ? state.activeBucket : ''));