diff --git a/crates/loro-core/src/dag.rs b/crates/loro-core/src/dag.rs
index f28ad7eb..ee723438 100644
--- a/crates/loro-core/src/dag.rs
+++ b/crates/loro-core/src/dag.rs
@@ -353,24 +353,25 @@ where
             }
         }
 
-        // if top nodes are from the same client with different source, we find a shared node
-        if let Some((other_node, other_type)) = queue.peek() {
-            if node_type != *other_type && node.id.client_id == other_node.id.client_id {
-                if node_type != NodeType::Shared {
-                    ans.push(ID {
-                        client_id: node.id.client_id,
-                        counter: node.id.counter.min(other_node.id.counter),
-                    });
-                    node_type = NodeType::Shared;
-                }
-                match other_type {
-                    NodeType::A => a_count -= 1,
-                    NodeType::B => b_count -= 1,
-                    NodeType::Shared => {}
-                }
-                queue.pop();
-            }
-        }
+        // // if top nodes are from the same client with different source, we find a shared node
+        // if let Some((other_node, other_type)) = queue.peek() {
+        //     if node_type != *other_type && node.id.client_id == other_node.id.client_id {
+        //         if node_type != NodeType::Shared {
+        //             debug_assert!(other_node.id.counter < node.id.counter);
+        //             ans.push(ID {
+        //                 client_id: node.id.client_id,
+        //                 counter: other_node.id.counter,
+        //             });
+        //             node_type = NodeType::Shared;
+        //         }
+        //         match other_type {
+        //             NodeType::A => a_count -= 1,
+        //             NodeType::B => b_count -= 1,
+        //             NodeType::Shared => {}
+        //         }
+        //         queue.pop();
+        //     }
+        // }
 
         // detect whether client is visited by other
         if let Some((ctr, visited_type)) = visited.get_mut(&node.id.client_id) {
diff --git a/crates/loro-core/src/dag/test.rs b/crates/loro-core/src/dag/test.rs
index 424b71b4..5dd6d001 100644
--- a/crates/loro-core/src/dag/test.rs
+++ b/crates/loro-core/src/dag/test.rs
@@ -580,12 +580,12 @@ mod find_common_ancestors_proptest {
     fn issue() {
         if let Err(err) = test_mul_ancestors::<3>(
             10,
-            vec![],
             vec![Interaction {
-                dag_idx: 4,
-                merge_with: Some(2),
+                dag_idx: 2,
+                merge_with: Some(5),
                 len: 1,
             }],
+            vec![],
         ) {
             println!("{}", err);
             panic!();
@@ -681,7 +681,18 @@ mod find_common_ancestors_proptest {
             dags.push(TestDag::new(i as ClientID));
         }
 
-        for interaction in before_merge_insertion {
+        for mut interaction in before_merge_insertion {
+            if interaction.dag_idx < N {
+                // cannot act on first N nodes
+                interaction.dag_idx = interaction.dag_idx % (dags.len() - N) + N;
+            }
+            if let Some(merge) = interaction.merge_with {
+                if interaction.dag_idx == merge {
+                    let next_merge = (merge + 1) % dags.len();
+                    interaction.merge_with = Some(next_merge);
+                }
+            }
+
             apply(interaction, &mut dags);
         }