diff --git a/examples/hex-game/README.md b/examples/hex-game/README.md
index 2e65ce11634..bafab18794c 100644
--- a/examples/hex-game/README.md
+++ b/examples/hex-game/README.md
@@ -74,7 +74,7 @@ sleep 1
 The `start` mutation starts a new game. We specify the two players using their new public keys,
 on [`http://localhost:8080/chains/$CHAIN_1/applications/$APP_ID`][main_chain]:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
   start(
     players: [
@@ -89,7 +89,7 @@ mutation {
 
 The app's main chain keeps track of the games in progress, by public key:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query {
   gameChains {
     keys(count: 3)
@@ -99,7 +99,7 @@ query {
 
 It contains the temporary chain's ID, and the ID of the message that created it:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query {
   gameChains {
     entry(key: "8a21aedaef74697db8b676c3e03ddf965bf4a808dc2bcabb6d70d6e6e3022ff7") {
diff --git a/examples/hex-game/src/lib.rs b/examples/hex-game/src/lib.rs
index 1186b25e6e0..5f2ba50e52e 100644
--- a/examples/hex-game/src/lib.rs
+++ b/examples/hex-game/src/lib.rs
@@ -78,7 +78,7 @@ sleep 1
 The `start` mutation starts a new game. We specify the two players using their new public keys,
 on [`http://localhost:8080/chains/$CHAIN_1/applications/$APP_ID`][main_chain]:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
   start(
     players: [
@@ -93,7 +93,7 @@ mutation {
 
 The app's main chain keeps track of the games in progress, by public key:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query {
   gameChains {
     keys(count: 3)
@@ -103,7 +103,7 @@ query {
 
 It contains the temporary chain's ID, and the ID of the message that created it:
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query {
   gameChains {
     entry(key: "8a21aedaef74697db8b676c3e03ddf965bf4a808dc2bcabb6d70d6e6e3022ff7") {
diff --git a/examples/social/README.md b/examples/social/README.md
index 5e2d7f14fb4..7339b5664c7 100644
--- a/examples/social/README.md
+++ b/examples/social/README.md
@@ -53,7 +53,7 @@ linera --with-wallet 0 project publish-and-create examples/social
 This will output the new application ID, e.g.:
 
 ```rust
-e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 ```
 
 With the `wallet show` command you can find the ID of the application creator's chain:
@@ -88,7 +88,7 @@ one of the chain where it isn't registered yet:
 mutation {
     requestApplication(
         chainId: "1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03",
-        applicationId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000"
+        applicationId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000"
     )
 }
 ```
@@ -108,10 +108,10 @@ query {
 ```
 
 Open both URLs under the entry `link`. Now you can use the application on each chain.
-E.g. [in the 8081 tab](http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000)
+E.g. [in the 8081 tab](http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000)
 subscribe to the other chain:
 
-```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
     subscribe(
         chainId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65"
@@ -119,9 +119,9 @@ mutation {
 }
 ```
 
-Now make a post [in the 8080 tab](http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000):
+Now make a post [in the 8080 tab](http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000):
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
     post(
         text: "Linera Social is the new Mastodon!"
@@ -132,7 +132,7 @@ mutation {
 
 Since 8081 is a subscriber. Let's see if it received any posts: # You can see the post on running the [web-frontend](./web-frontend/), or follow the steps below.
 
-```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query { receivedPosts { keys { timestamp author index } } }
 ```
 
diff --git a/examples/social/src/lib.rs b/examples/social/src/lib.rs
index f59f806783e..55841171f5f 100644
--- a/examples/social/src/lib.rs
+++ b/examples/social/src/lib.rs
@@ -62,7 +62,7 @@ linera --with-wallet 0 project publish-and-create examples/social
 This will output the new application ID, e.g.:
 
 ```ignore
-e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 ```
 
 With the `wallet show` command you can find the ID of the application creator's chain:
@@ -97,7 +97,7 @@ one of the chain where it isn't registered yet:
 mutation {
     requestApplication(
         chainId: "1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03",
-        applicationId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000"
+        applicationId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000"
     )
 }
 ```
@@ -117,10 +117,10 @@ query {
 ```
 
 Open both URLs under the entry `link`. Now you can use the application on each chain.
-E.g. [in the 8081 tab](http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000)
+E.g. [in the 8081 tab](http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000)
 subscribe to the other chain:
 
-```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
     subscribe(
         chainId: "e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65"
@@ -128,9 +128,9 @@ mutation {
 }
 ```
 
-Now make a post [in the 8080 tab](http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000):
+Now make a post [in the 8080 tab](http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000):
 
-```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8080/chains/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 mutation {
     post(
         text: "Linera Social is the new Mastodon!"
@@ -141,7 +141,7 @@ mutation {
 
 Since 8081 is a subscriber. Let's see if it received any posts: # You can see the post on running the [web-frontend](./web-frontend/), or follow the steps below.
 
-```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000001000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
+```gql,uri=http://localhost:8081/chains/1db1936dad0717597a7743a8353c9c0191c14c3a129b258e9743aec2b4f05d03/applications/e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65010000000000000000000000e476187f6ddfeb9d588c7b45d3df334d5501d6499b3f9ad5595cae86cce16a65030000000000000000000000
 query { receivedPosts { keys { timestamp author index } } }
 ```
 
diff --git a/linera-chain/src/chain.rs b/linera-chain/src/chain.rs
index 6fb695c043c..76a93df084e 100644
--- a/linera-chain/src/chain.rs
+++ b/linera-chain/src/chain.rs
@@ -1182,16 +1182,15 @@ where
         }
         let full_names = raw_outcome
             .subscribe
-            .clone()
-            .into_iter()
+            .iter()
             .map(|(name, _id)| ChannelFullName {
                 application_id,
-                name,
+                name: name.clone(),
             })
             .collect::<Vec<_>>();
         let channels = self.channels.try_load_entries_mut(&full_names).await?;
-        let stream = raw_outcome.subscribe.into_iter().zip(channels);
-        let stream = stream::iter(stream)
+        let subscribe_channels = raw_outcome.subscribe.into_iter().zip(channels);
+        let stream = stream::iter(subscribe_channels)
             .map(|((name, id), mut channel)| async move {
                 let mut result = None;
                 let full_name = ChannelFullName {
diff --git a/linera-core/src/unit_tests/wasm_worker_tests.rs b/linera-core/src/unit_tests/wasm_worker_tests.rs
index b9bc02ed78c..7d2aae9ebdd 100644
--- a/linera-core/src/unit_tests/wasm_worker_tests.rs
+++ b/linera-core/src/unit_tests/wasm_worker_tests.rs
@@ -339,16 +339,7 @@ where
     let publisher_state_hash = publisher_system_state.into_hash().await;
     let accept_block_proposal = HashedCertificateValue::new_confirmed(
         BlockExecutionOutcome {
-            messages: vec![vec![OutgoingMessage {
-                destination: Destination::Recipient(creator_chain.into()),
-                authenticated_signer: None,
-                grant: Amount::ZERO,
-                refund_grant_to: None,
-                kind: MessageKind::Protected,
-                message: Message::System(SystemMessage::Notify {
-                    id: creator_chain.into(),
-                }),
-            }]],
+            messages: vec![Vec::new()],
             events: vec![Vec::new()],
             state_hash: publisher_state_hash,
             oracle_responses: vec![Vec::new()],
diff --git a/linera-core/src/unit_tests/worker_tests.rs b/linera-core/src/unit_tests/worker_tests.rs
index 809dcde0480..6808117b0f3 100644
--- a/linera-core/src/unit_tests/worker_tests.rs
+++ b/linera-core/src/unit_tests/worker_tests.rs
@@ -2399,11 +2399,7 @@ where
         &worker,
         HashedCertificateValue::new_confirmed(
             BlockExecutionOutcome {
-                messages: vec![vec![direct_outgoing_message(
-                    user_id,
-                    MessageKind::Protected,
-                    SystemMessage::Notify { id: user_id },
-                )]],
+                messages: vec![Vec::new()],
                 events: vec![Vec::new()],
                 state_hash: SystemExecutionState {
                     // The root chain knows both committees at the end.
@@ -2489,13 +2485,11 @@ where
                 .added_bundles
                 .read_front(10)
                 .await?[..],
-            [bundle1, bundle2, bundle3]
+            [bundle1, bundle2]
             if matches!(bundle1.messages[..], [PostedMessage {
                  message: Message::System(SystemMessage::OpenChain(_)), ..
             }]) && matches!(bundle2.messages[..], [PostedMessage {
                 message: Message::System(SystemMessage::Credit { .. }), ..
-            }]) && matches!(bundle3.messages[..], [PostedMessage {
-                message: Message::System(SystemMessage::Notify { .. }), ..
             }])
         );
         let channel_inbox = user_chain
@@ -2517,8 +2511,8 @@ where
         &worker,
         HashedCertificateValue::new_confirmed(
             BlockExecutionOutcome {
-                messages: vec![Vec::new(); 4],
-                events: vec![Vec::new(); 4],
+                messages: vec![Vec::new(); 3],
+                events: vec![Vec::new(); 3],
                 state_hash: SystemExecutionState {
                     subscriptions: [ChannelSubscription {
                         chain_id: admin_id,
@@ -2534,7 +2528,7 @@ where
                 }
                 .into_hash()
                 .await,
-                oracle_responses: vec![Vec::new(); 4],
+                oracle_responses: vec![Vec::new(); 3],
             }
             .with(
                 make_first_block(user_id)
@@ -2585,18 +2579,6 @@ where
                                 .to_posted(1, MessageKind::Tracked)],
                         },
                         action: MessageAction::Accept,
-                    })
-                    .with_incoming_bundle(IncomingBundle {
-                        origin: Origin::chain(admin_id),
-                        bundle: MessageBundle {
-                            certificate_hash: certificate2.value.hash(),
-                            height: BlockHeight::from(2),
-                            timestamp: Timestamp::from(0),
-                            transaction_index: 0,
-                            messages: vec![Message::System(SystemMessage::Notify { id: user_id })
-                                .to_posted(0, MessageKind::Protected)],
-                        },
-                        action: MessageAction::Accept,
                     }),
             ),
         ),
@@ -2633,7 +2615,7 @@ where
                 .try_load_entry(&Origin::chain(admin_id))
                 .await?
                 .expect("Missing inbox for admin chain in user chain");
-            assert_eq!(inbox.next_block_height_to_receive()?, BlockHeight(3));
+            assert_eq!(inbox.next_block_height_to_receive()?, BlockHeight(2));
             assert_eq!(inbox.added_bundles.count(), 0);
             assert_eq!(inbox.removed_bundles.count(), 0);
         }
diff --git a/linera-execution/src/system.rs b/linera-execution/src/system.rs
index 02300fef99e..cff5aa144cb 100644
--- a/linera-execution/src/system.rs
+++ b/linera-execution/src/system.rs
@@ -247,8 +247,6 @@ pub enum SystemMessage {
     RegisterApplications {
         applications: Vec<UserApplicationDescription>,
     },
-    /// Does nothing. Used to debug the intended recipients of a block.
-    Notify { id: ChainId },
     /// Requests a `RegisterApplication` message from the target chain to register the specified
     /// application on the sender chain.
     RequestApplication(UserApplicationId),
@@ -281,7 +279,6 @@ impl SystemMessage {
             | SystemMessage::Subscribe { .. }
             | SystemMessage::Unsubscribe { .. }
             | SystemMessage::ApplicationCreated
-            | SystemMessage::Notify { .. }
             | SystemMessage::RequestApplication(_) => Box::new(iter::empty()),
         }
     }
@@ -874,16 +871,6 @@ where
                     subscription.chain_id == context.chain_id,
                     SystemExecutionError::IncorrectChainId(subscription.chain_id)
                 );
-                // Notify the subscriber about this block, so that it is included in the
-                // received_log of the subscriber and correctly synchronized.
-                let message = RawOutgoingMessage {
-                    destination: Destination::Recipient(id),
-                    authenticated: false,
-                    grant: Amount::ZERO,
-                    kind: MessageKind::Protected,
-                    message: SystemMessage::Notify { id },
-                };
-                outcome.messages.push(message);
                 outcome.subscribe.push((subscription.name.clone(), id));
             }
             Unsubscribe { id, subscription } => {
@@ -891,14 +878,6 @@ where
                     subscription.chain_id == context.chain_id,
                     SystemExecutionError::IncorrectChainId(subscription.chain_id)
                 );
-                let message = RawOutgoingMessage {
-                    destination: Destination::Recipient(id),
-                    authenticated: false,
-                    grant: Amount::ZERO,
-                    kind: MessageKind::Protected,
-                    message: SystemMessage::Notify { id },
-                };
-                outcome.messages.push(message);
                 outcome.unsubscribe.push((subscription.name.clone(), id));
             }
             BytecodePublished { transaction_index } => {
@@ -951,7 +930,7 @@ where
             OpenChain(_) => {
                 // This special message is executed immediately when cross-chain requests are received.
             }
-            ApplicationCreated | Notify { .. } => (),
+            ApplicationCreated => (),
         }
         Ok(outcome)
     }
@@ -1061,7 +1040,7 @@ where
         id: ChainId,
     ) -> Result<Vec<RawOutgoingMessage<SystemMessage, Amount>>, SystemExecutionError> {
         let mut messages = Vec::new();
-        // Unsubscribe to all channels.
+        // Unsubscribe from all channels.
         self.subscriptions
             .for_each_index(|subscription| {
                 let message = RawOutgoingMessage {
diff --git a/linera-rpc/tests/snapshots/format__format.yaml.snap b/linera-rpc/tests/snapshots/format__format.yaml.snap
index ace2ed3fab0..8aeec9011bb 100644
--- a/linera-rpc/tests/snapshots/format__format.yaml.snap
+++ b/linera-rpc/tests/snapshots/format__format.yaml.snap
@@ -923,11 +923,6 @@ SystemMessage:
               SEQ:
                 TYPENAME: UserApplicationDescription
     10:
-      Notify:
-        STRUCT:
-          - id:
-              TYPENAME: ChainId
-    11:
       RequestApplication:
         NEWTYPE:
           TYPENAME: ApplicationId
diff --git a/linera-sdk/src/test/chain.rs b/linera-sdk/src/test/chain.rs
index 6f28f041aad..5ddd88df981 100644
--- a/linera-sdk/src/test/chain.rs
+++ b/linera-sdk/src/test/chain.rs
@@ -326,7 +326,7 @@ impl ActiveChain {
             })
             .await;
 
-        assert_eq!(accept_certificate.outgoing_message_count(), 1);
+        assert_eq!(accept_certificate.outgoing_message_count(), 0);
 
         self.add_block(|block| {
             block.with_system_messages_from(&accept_certificate, SystemChannel::PublishedBytecodes);