Fix bug

src/models/note.ts

@@ -286,7 +286,7 @@ export const pack = async (
 					_id: -1
 				}
 			});
-			return prev ? prev._id : null;
+			return prev ? prev._id.toHexString() : null;
 		})();
 
 		// Get next note info
@@ -304,7 +304,7 @@ export const pack = async (
 					_id: 1
 				}
 			});
-			return next ? next._id : null;
+			return next ? next._id.toHexString() : null;
 		})();
 
 		if (_note.replyId) {

src/server/web/views/note.pug

@@ -21,6 +21,6 @@ block meta
 	meta(property='og:image'       content= img)
 
 	if note.prev
-		link(rel='prev' href=`${config.url}/notes/${note.prev.id}`)
+		link(rel='prev' href=`${config.url}/notes/${note.prev}`)
 	if note.next
-		link(rel='next' href=`${config.url}/notes/${note.next.id}`)
+		link(rel='next' href=`${config.url}/notes/${note.next}`)