:art: fix https://github.com/siyuan-note/siyuan/issues/10067

app/src/protyle/render/av/cell.ts

@@ -595,7 +595,7 @@ const renderRollup = (cellValue: IAVCellValue) => {
         if (cellValue?.isDetached) {
             text = `<span class="av__celltext">${cellValue.block?.content || ""}</span>`;
         } else {
-            text = `<span data-type="block-ref" data-id="${cellValue.block?.id}" data-subtype="s" class="av__celltext av__celltext--ref">${cellValue.block?.content || ""}</span>`;
+            text = `<span data-type="block-ref" data-id="${cellValue.block?.id}" data-subtype="s" class="av__celltext av__celltext--ref">${cellValue.block?.content || "Untitled"}</span>`;
         }
     } else if (cellValue.type === "number") {
         text = cellValue?.number.formattedContent || cellValue?.number.content.toString() || "";