diff --git a/crates/loro-internal/src/arena.rs b/crates/loro-internal/src/arena.rs
index 316e5697..f1bdd75a 100644
--- a/crates/loro-internal/src/arena.rs
+++ b/crates/loro-internal/src/arena.rs
@@ -391,7 +391,7 @@ impl SharedArena {
                 container,
                 content: crate::op::InnerContent::Future(crate::op::FutureInnerContent::Unknown {
                     prop,
-                    value,
+                    value: Box::new(value),
                 }),
             },
         }
diff --git a/crates/loro-internal/src/encoding/encode_reordered.rs b/crates/loro-internal/src/encoding/encode_reordered.rs
index 4612b1ca..3d471521 100644
--- a/crates/loro-internal/src/encoding/encode_reordered.rs
+++ b/crates/loro-internal/src/encoding/encode_reordered.rs
@@ -1448,7 +1448,7 @@ pub(crate) fn decode_op(
         // NOTE: The future container type need also try to parse the unknown type
         ContainerType::Unknown(_) => crate::op::InnerContent::Future(FutureInnerContent::Unknown {
             prop,
-            value: value.into_owned(),
+            value: Box::new(value.into_owned()),
         }),
     };
 
diff --git a/crates/loro-internal/src/encoding/json_schema.rs b/crates/loro-internal/src/encoding/json_schema.rs
index 831d60f5..ec91a442 100644
--- a/crates/loro-internal/src/encoding/json_schema.rs
+++ b/crates/loro-internal/src/encoding/json_schema.rs
@@ -378,7 +378,7 @@ fn encode_changes(
                     };
                     JsonOpContent::Future(op::FutureOpWrapper {
                         prop: *prop,
-                        value: op::FutureOp::Unknown(value.clone()),
+                        value: op::FutureOp::Unknown((**value).clone()),
                     })
                 }
                 #[cfg(feature = "counter")]
@@ -626,7 +626,10 @@ fn decode_op(op: op::JsonOp, arena: &SharedArena, peers: &[PeerID]) -> LoroResul
             JsonOpContent::Future(op::FutureOpWrapper {
                 prop,
                 value: op::FutureOp::Unknown(value),
-            }) => InnerContent::Future(FutureInnerContent::Unknown { prop, value }),
+            }) => InnerContent::Future(FutureInnerContent::Unknown {
+                prop,
+                value: Box::new(value),
+            }),
             _ => unreachable!(),
         },
         #[cfg(feature = "counter")]
diff --git a/crates/loro-internal/src/op/content.rs b/crates/loro-internal/src/op/content.rs
index eeee7769..fae23fa9 100644
--- a/crates/loro-internal/src/op/content.rs
+++ b/crates/loro-internal/src/op/content.rs
@@ -83,7 +83,7 @@ pub enum FutureInnerContent {
     Counter(f64),
     Unknown {
         prop: i32,
-        value: OwnedValue,
+        value: Box<OwnedValue>,
     },
 }
 impl FutureInnerContent {
diff --git a/crates/loro-internal/src/oplog.rs b/crates/loro-internal/src/oplog.rs
index 18b784bc..8af42d28 100644
--- a/crates/loro-internal/src/oplog.rs
+++ b/crates/loro-internal/src/oplog.rs
@@ -933,7 +933,7 @@ pub(crate) fn local_op_to_remote(
             FutureInnerContent::Unknown { prop, value } => {
                 contents.push(crate::op::RawOpContent::Unknown {
                     prop: *prop,
-                    value: value.clone(),
+                    value: (**value).clone(),
                 })
             }
         },