diff --git a/test/test-cid.spec.js b/test/test-cid.spec.js
index 47754aa8..d203c17d 100644
--- a/test/test-cid.spec.js
+++ b/test/test-cid.spec.js
@@ -704,4 +704,14 @@ describe('CID', () => {
     assert.isFalse(Object.keys(cid).includes('asCID'))
     assert.equal(cid.asCID, cid)
   })
+
+  it('CID can be moved across JS realms', async () => {
+    const cid = CID.parse('bafybeif2pall7dybz7vecqka3zo24irdwabwdi4wc55jznaq75q7eaavvu')
+    const { port1: sender, port2: receiver } = new MessageChannel()
+    sender.postMessage(cid)
+    const cid2 = await new Promise((resolve) => {
+      receiver.onmessage = (event) => { resolve(event.data) }
+    })
+    assert.equal(cid2.asCID, cid2)
+  })
 })