diff --git a/src/vanilla.ts b/src/vanilla.ts
index 19490210..b6698b06 100644
--- a/src/vanilla.ts
+++ b/src/vanilla.ts
@@ -115,7 +115,8 @@ const createSnapshotDefault = <T extends object>(
     }
     Object.defineProperty(snap, key, desc)
   })
-  return Object.preventExtensions(snap)
+  // Object.preventExtensions is removed. ref: https://github.com/pmndrs/valtio/pull/1220
+  return snap
 }
 
 const createHandlerDefault = <T extends object>(
diff --git a/tests/snapshot.test.ts b/tests/snapshot.test.ts
index 53c356bd..7a20a961 100644
--- a/tests/snapshot.test.ts
+++ b/tests/snapshot.test.ts
@@ -24,26 +24,6 @@ describe('snapshot', () => {
     expect(snap1).toBe(snap2)
   })
 
-  it('should make the snapshot immutable', () => {
-    const state = proxy<{ foo: number; bar?: string }>({ foo: 1 })
-    const snap = snapshot(state)
-
-    // Overwriting existing property
-    expect(() => {
-      ;(snap as typeof state).foo = 100
-    }).toThrow()
-
-    // Extension (adding new property)
-    expect(() => {
-      ;(snap as typeof state).bar = 'hello'
-    }).toThrow()
-
-    // Note: The current implementation does not prevent property removal.
-    // Do not add a test for this unless we come up with an implementation that
-    // supports it.
-    // See https://github.com/pmndrs/valtio/issues/749
-  })
-
   it('should not cause proxy-compare to copy', async () => {
     const state = proxy({ foo: 1 })
     const snap1 = snapshot(state)