test: update protocol fixtures

9 files changed, 89 insertions, 76 deletions

diff --git a/src/api/schema.rs b/src/api/schema.rs
index 0b801d89..cfd681ca 100644
--- a/src/api/schema.rs
+++ b/src/api/schema.rs
@@ -994,7 +994,7 @@ mod tests {
             id: "req_1".into(),
             result: ResponseResult::Pong {
                 version: "0.1.2".into(),
-                protocol: 4,
+                protocol: 5,
             },
         };
 
diff --git a/tests/cli_wrapper.rs b/tests/cli_wrapper.rs
index 473a6934..357482e9 100644
--- a/tests/cli_wrapper.rs
+++ b/tests/cli_wrapper.rs
@@ -938,7 +938,7 @@ fn status_commands_report_client_and_server_versions() {
         "stdout: {full_stdout}"
     );
     assert!(
-        full_stdout.contains("  protocol: 4"),
+        full_stdout.contains("  protocol: 5"),
         "stdout: {full_stdout}"
     );
     assert!(full_stdout.contains("server:\n"), "stdout: {full_stdout}");
@@ -971,7 +971,7 @@ fn status_commands_report_client_and_server_versions() {
         "stdout: {server_stdout}"
     );
     assert!(
-        server_stdout.contains("protocol: 4"),
+        server_stdout.contains("protocol: 5"),
         "stdout: {server_stdout}"
     );
 
@@ -983,7 +983,7 @@ fn status_commands_report_client_and_server_versions() {
         "stdout: {client_stdout}"
     );
     assert!(
-        client_stdout.contains("protocol: 4"),
+        client_stdout.contains("protocol: 5"),
         "stdout: {client_stdout}"
     );
     assert!(
diff --git a/tests/client_mode.rs b/tests/client_mode.rs
index 8aea0dda..25e7d42c 100644
--- a/tests/client_mode.rs
+++ b/tests/client_mode.rs
@@ -167,6 +167,7 @@ struct FrameWire {
     height: u16,
     cursor: Option<CursorWire>,
     hyperlinks: Vec<String>,
+    graphics: Vec<u8>,
 }
 
 #[allow(dead_code)]
@@ -219,7 +220,7 @@ fn frame_contains_text(frame: &FrameWire, needle: &str) -> bool {
         }
         text.push('\n');
     }
-    let _ = frame.height;
+    let _ = (frame.height, frame.graphics.len());
     if let Some(cursor) = frame.cursor.as_ref() {
         let _ = (cursor.x, cursor.y, cursor.visible);
     }
@@ -250,8 +251,8 @@ fn client_connects_and_receives_frame() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4, "server should report protocol version 4");
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5, "server should report protocol version 5");
     assert!(
         error.is_none(),
         "handshake should not have error: {:?}",
@@ -330,8 +331,8 @@ fn client_sees_headless_startup_config_diagnostic() {
 
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     stream
@@ -379,8 +380,8 @@ fn client_input_forwarded_to_pane() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Send an Input message containing "echo hello\n".
@@ -433,8 +434,8 @@ fn client_resize_sends_message() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain the initial frame(s).
@@ -443,11 +444,13 @@ fn client_resize_sends_message() {
         .unwrap();
     while read_server_message(&mut stream).is_ok() {}
 
-    // Send a Resize message: ClientMessage::Resize is variant 2: { cols: u16, rows: u16 }
+    // Send a Resize message: ClientMessage::Resize is variant 2.
     let resize_payload = {
         let mut buf = encode_varint_u32(2); // variant 2 = Resize
         buf.extend_from_slice(&encode_varint_u16(120)); // cols
         buf.extend_from_slice(&encode_varint_u16(40)); // rows
+        buf.extend_from_slice(&encode_varint_u32(8)); // cell_width_px
+        buf.extend_from_slice(&encode_varint_u32(16)); // cell_height_px
         buf
     };
     let framed = frame_message(&resize_payload);
@@ -490,8 +493,8 @@ fn server_shutdown_sends_message_to_client() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Send SIGINT so the server takes the graceful shutdown path and
@@ -718,8 +721,8 @@ fn client_receives_frame_after_pane_output() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Read the initial frame (server renders immediately on client connect).
@@ -772,8 +775,8 @@ fn navigate_mode_keybind_dispatch_in_server() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -890,8 +893,8 @@ fn graceful_shutdown_sends_server_shutdown_to_client() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frame(s).
@@ -907,7 +910,7 @@ fn graceful_shutdown_sends_server_shutdown_to_client() {
         }
     }
 
-    // The client should receive a ServerShutdown message (variant 3)
+    // The client should receive a ServerShutdown message (variant 4)
     // before the connection is closed, not just an abrupt EOF.
     stream
         .set_read_timeout(Some(Duration::from_secs(5)))
@@ -916,8 +919,8 @@ fn graceful_shutdown_sends_server_shutdown_to_client() {
     match result {
         Ok((variant, _payload)) => {
             assert_eq!(
-                variant, 3,
-                "expected ServerShutdown (variant 3), got variant {variant}"
+                variant, 4,
+                "expected ServerShutdown (variant 4), got variant {variant}"
             );
         }
         Err(e) => {
@@ -988,8 +991,8 @@ fn client_receives_notify_on_agent_state_change() {
     // Connect as a client and perform handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frame(s).
@@ -1040,8 +1043,8 @@ fn client_receives_notify_on_agent_state_change() {
     let mut report_response = String::new();
     report_reader.read_line(&mut report_response).unwrap();
 
-    // Read messages from the client stream and look for Notify (variant 4).
-    // Notify = ServerMessage variant index 4 (after Welcome=0, Frame=1, Terminal=2, ServerShutdown=3).
+    // Read messages from the client stream and look for Notify (variant 5).
+    // Notify = ServerMessage variant index 5.
     stream
         .set_read_timeout(Some(Duration::from_secs(5)))
         .unwrap();
@@ -1050,7 +1053,7 @@ fn client_receives_notify_on_agent_state_change() {
     while Instant::now() < deadline {
         match read_server_message(&mut stream) {
             Ok((variant, _payload)) => {
-                if variant == 4 {
+                if variant == 5 {
                     // ServerMessage::Notify — found it!
                     found_notify = true;
                     break;
@@ -1136,7 +1139,7 @@ fn client_receives_notify_on_agent_state_change() {
     while Instant::now() < deadline {
         match read_server_message(&mut stream) {
             Ok((variant, _payload)) => {
-                if variant == 4 {
+                if variant == 5 {
                     // Found a Notify message — that's good enough.
                     // The test already verified the Blocked→Notify path above.
                     found_done_notify = true;
diff --git a/tests/cross_area.rs b/tests/cross_area.rs
index 3975d402..963214b3 100644
--- a/tests/cross_area.rs
+++ b/tests/cross_area.rs
@@ -417,6 +417,8 @@ fn client_handshake(stream: &mut UnixStream, version: u32, cols: u16, rows: u16)
     payload.extend_from_slice(&encode_varint_u32(version));
     payload.extend_from_slice(&encode_varint_u16(cols));
     payload.extend_from_slice(&encode_varint_u16(rows));
+    payload.extend_from_slice(&encode_varint_u32(8)); // cell_width_px
+    payload.extend_from_slice(&encode_varint_u32(16)); // cell_height_px
     payload.extend_from_slice(&encode_varint_u32(0)); // RenderEncoding::SemanticFrame
 
     stream
@@ -497,6 +499,7 @@ struct FrameWire {
     height: u16,
     cursor: Option<CursorWire>,
     hyperlinks: Vec<String>,
+    graphics: Vec<u8>,
 }
 
 #[allow(dead_code)]
@@ -549,7 +552,7 @@ fn frame_contains_text(frame: &FrameWire, needle: &str) -> bool {
         }
         text.push('\n');
     }
-    let _ = frame.height;
+    let _ = (frame.height, frame.graphics.len());
     if let Some(cursor) = frame.cursor.as_ref() {
         let _ = (cursor.x, cursor.y, cursor.visible);
     }
@@ -674,7 +677,7 @@ fn cross_area_detach_and_reattach_preserves_state() {
 
     // Local attach (client A).
     let mut client_a = UnixStream::connect(&client_socket).expect("client A should connect");
-    client_handshake(&mut client_a, 4, 100, 30);
+    client_handshake(&mut client_a, 5, 100, 30);
     assert!(wait_for_frame(&mut client_a, Duration::from_secs(2)));
 
     // Use herdr: create a workspace and write output into its pane.
@@ -711,7 +714,7 @@ fn cross_area_detach_and_reattach_preserves_state() {
 
     // Reattach from another terminal/session (client B).
     let mut client_b = UnixStream::connect(&client_socket).expect("client B should connect");
-    client_handshake(&mut client_b, 4, 80, 24);
+    client_handshake(&mut client_b, 5, 80, 24);
     assert!(
         wait_for_frame(&mut client_b, Duration::from_secs(5)),
         "reattached client should receive frame"
@@ -767,7 +770,7 @@ fn cross_area_agent_process_survives_detach_and_reattach() {
     wait_for_socket(&client_socket, Duration::from_secs(10));
 
     let mut client_a = UnixStream::connect(&client_socket).expect("client A should connect");
-    client_handshake(&mut client_a, 4, 100, 30);
+    client_handshake(&mut client_a, 5, 100, 30);
     assert!(wait_for_frame(&mut client_a, Duration::from_secs(2)));
 
     let created = workspace_create(&api_socket, "agent-persist");
@@ -820,7 +823,7 @@ fn cross_area_agent_process_survives_detach_and_reattach() {
 
     // Reattach and ensure client-side state reflects the persisted working status.
     let mut client_b = UnixStream::connect(&client_socket).expect("client B should connect");
-    client_handshake(&mut client_b, 4, 80, 24);
+    client_handshake(&mut client_b, 5, 80, 24);
     let saw_working_on_client =
         wait_for_frame_matching(&mut client_b, Duration::from_secs(5), |frame| {
             frame_contains_text(frame, "working")
@@ -865,7 +868,7 @@ fn cross_area_client_and_api_workspace_views_are_consistent() {
     wait_for_socket(&client_socket, Duration::from_secs(10));
 
     let mut client = UnixStream::connect(&client_socket).expect("client should connect");
-    client_handshake(&mut client, 4, 100, 30);
+    client_handshake(&mut client, 5, 100, 30);
     assert!(wait_for_frame(&mut client, Duration::from_secs(2)));
     drain_server_messages(&mut client, Duration::from_millis(300));
 
@@ -928,9 +931,9 @@ fn cross_area_two_clients_shared_view_and_single_detach_stability() {
     wait_for_socket(&client_socket, Duration::from_secs(10));
 
     let mut client_a = UnixStream::connect(&client_socket).expect("client A should connect");
-    client_handshake(&mut client_a, 4, 110, 30);
+    client_handshake(&mut client_a, 5, 110, 30);
     let mut client_b = UnixStream::connect(&client_socket).expect("client B should connect");
-    client_handshake(&mut client_b, 4, 100, 30);
+    client_handshake(&mut client_b, 5, 100, 30);
 
     assert!(wait_for_frame(&mut client_a, Duration::from_secs(2)));
     assert!(wait_for_frame(&mut client_b, Duration::from_secs(2)));
@@ -1096,7 +1099,7 @@ fn cross_area_server_kill_then_restart_and_reconnect() {
 
     let mut reconnect_client =
         UnixStream::connect(&client_socket).expect("new client should connect after restart");
-    client_handshake(&mut reconnect_client, 4, 80, 24);
+    client_handshake(&mut reconnect_client, 5, 80, 24);
     assert!(
         wait_for_frame(&mut reconnect_client, Duration::from_secs(5)),
         "new client should receive frame after restart"
diff --git a/tests/detach_reattach.rs b/tests/detach_reattach.rs
index 519c2ca2..588d5713 100644
--- a/tests/detach_reattach.rs
+++ b/tests/detach_reattach.rs
@@ -276,8 +276,8 @@ fn navigate_q_detaches_client_and_server_persists() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -338,8 +338,8 @@ fn explicit_detach_message_causes_clean_disconnect() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -397,8 +397,8 @@ fn reattach_after_detach_shows_current_state() {
     // --- Client A ---
     let mut stream_a = UnixStream::connect(&client_socket).expect("client A should connect");
     let (version, error) =
-        client_handshake(&mut stream_a, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_a, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -436,8 +436,8 @@ fn reattach_after_detach_shows_current_state() {
     // --- Client B (reattach) ---
     let mut stream_b = UnixStream::connect(&client_socket).expect("client B should connect");
     let (version, error) =
-        client_handshake(&mut stream_b, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_b, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(
         error.is_none(),
         "reattach handshake should succeed: {:?}",
@@ -516,8 +516,8 @@ fn processes_survive_during_and_after_detach() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -555,8 +555,8 @@ fn processes_survive_during_and_after_detach() {
     // Reattach — verify we can connect and receive a frame.
     let mut stream_b = UnixStream::connect(&client_socket).expect("should reattach");
     let (version, error) =
-        client_handshake(&mut stream_b, 4, 80, 24).expect("reattach handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_b, 5, 80, 24).expect("reattach handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Verify the reattached client receives a frame.
@@ -604,8 +604,8 @@ fn server_persists_after_client_connection_drop() {
     // Connect and handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect");
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Drain initial frames.
@@ -631,8 +631,8 @@ fn server_persists_after_client_connection_drop() {
     // Reattach — verify we can connect and handshake again.
     let mut stream_b = UnixStream::connect(&client_socket).expect("should reattach");
     let (version, error) =
-        client_handshake(&mut stream_b, 4, 80, 24).expect("reattach handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_b, 5, 80, 24).expect("reattach handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "reattach should succeed: {:?}", error);
 
     cleanup_spawned_herdr(spawned, base);
@@ -653,8 +653,8 @@ fn detached_output_preserves_last_attached_pty_size() {
 
     let mut stream = UnixStream::connect(&client_socket).expect("client should connect");
     let (version, error) =
-        client_handshake(&mut stream, 4, 120, 40).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream, 5, 120, 40).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
     drain_messages(&mut stream);
 
@@ -722,8 +722,8 @@ fn output_accumulated_while_detached_visible_on_reattach() {
     // Connect and handshake client A.
     let mut stream_a = UnixStream::connect(&client_socket).expect("client A should connect");
     let (version, error) =
-        client_handshake(&mut stream_a, 4, 80, 24).expect("handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_a, 5, 80, 24).expect("handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Detach client A immediately.
@@ -780,8 +780,8 @@ fn output_accumulated_while_detached_visible_on_reattach() {
     // --- Client B (reattach) ---
     let mut stream_b = UnixStream::connect(&client_socket).expect("client B should connect");
     let (version, error) =
-        client_handshake(&mut stream_b, 4, 80, 24).expect("reattach handshake should succeed");
-    assert_eq!(version, 4);
+        client_handshake(&mut stream_b, 5, 80, 24).expect("reattach handshake should succeed");
+    assert_eq!(version, 5);
     assert!(error.is_none(), "{:?}", error);
 
     // Client B should receive a frame with the current state.
diff --git a/tests/multi_client.rs b/tests/multi_client.rs
index b74e527c..704b511e 100644
--- a/tests/multi_client.rs
+++ b/tests/multi_client.rs
@@ -496,7 +496,9 @@ fn client_handshake(
             &encode_varint_u32(version),
             &encode_varint_u16(cols),
             &encode_varint_u16(rows),
-            &encode_varint_u32(0), // RenderEncoding::SemanticFrame
+            &encode_varint_u32(8),  // cell_width_px
+            &encode_varint_u32(16), // cell_height_px
+            &encode_varint_u32(0),  // RenderEncoding::SemanticFrame
         ],
     );
     stream
@@ -547,7 +549,7 @@ fn client_handshake(
 
 fn connect_raw_client(client_socket: &Path, cols: u16, rows: u16) -> UnixStream {
     let mut stream = UnixStream::connect(client_socket).expect("should connect to client socket");
-    client_handshake(&mut stream, 4, cols, rows).expect("handshake should succeed");
+    client_handshake(&mut stream, 5, cols, rows).expect("handshake should succeed");
     stream
 }
 
@@ -578,6 +580,7 @@ struct FrameWire {
     height: u16,
     cursor: Option<CursorWire>,
     hyperlinks: Vec<String>,
+    graphics: Vec<u8>,
 }
 
 #[allow(dead_code)]
@@ -709,7 +712,7 @@ fn frame_contains_text(frame: &FrameWire, needle: &str) -> bool {
         full_text.push('\n');
     }
 
-    let _ = frame.height;
+    let _ = (frame.height, frame.graphics.len());
     if let Some(cursor) = frame.cursor.as_ref() {
         let _ = (cursor.x, cursor.y, cursor.visible);
     }
diff --git a/tests/server_headless.rs b/tests/server_headless.rs
index 33a3fa7f..209a8045 100644
--- a/tests/server_headless.rs
+++ b/tests/server_headless.rs
@@ -169,7 +169,9 @@ fn client_handshake(
             &encode_varint_u32(version),
             &encode_varint_u16(cols),
             &encode_varint_u16(rows),
-            &encode_varint_u32(0), // RenderEncoding::SemanticFrame
+            &encode_varint_u32(8),  // cell_width_px
+            &encode_varint_u32(16), // cell_height_px
+            &encode_varint_u32(0),  // RenderEncoding::SemanticFrame
         ],
     );
     let framed = frame_message(&hello_payload);
@@ -581,11 +583,11 @@ fn client_handshake_succeeds() {
     // Connect to the client socket and perform a handshake.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
 
-    // Send Hello with version 4, 80 cols, 24 rows.
+    // Send Hello with version 5, 80 cols, 24 rows.
     let (version, error) =
-        client_handshake(&mut stream, 4, 80, 24).expect("handshake should succeed");
+        client_handshake(&mut stream, 5, 80, 24).expect("handshake should succeed");
 
-    assert_eq!(version, 4, "server should report protocol version 4");
+    assert_eq!(version, 5, "server should report protocol version 5");
     assert!(
         error.is_none(),
         "handshake should not have an error: {:?}",
@@ -614,7 +616,7 @@ fn client_handshake_rejects_incompatible_version() {
     let (version, error) = client_handshake(&mut stream, 0, 80, 24)
         .expect("should read Welcome response even on rejection");
 
-    assert_eq!(version, 4, "server should report its version 4");
+    assert_eq!(version, 5, "server should report its version 5");
     assert!(
         error.is_some(),
         "version 0 should be rejected with an error"
@@ -639,10 +641,10 @@ fn client_handshake_clamps_small_terminal_size() {
     // Send Hello with 0x0 terminal size — should be clamped.
     let mut stream = UnixStream::connect(&client_socket).expect("should connect to client socket");
 
-    let (version, error) = client_handshake(&mut stream, 4, 0, 0)
+    let (version, error) = client_handshake(&mut stream, 5, 0, 0)
         .expect("handshake with 0x0 should succeed (server clamps)");
 
-    assert_eq!(version, 4);
+    assert_eq!(version, 5);
     assert!(
         error.is_none(),
         "0x0 size should be accepted (clamped): {:?}",
@@ -702,9 +704,9 @@ fn no_hello_client_closed_within_five_seconds() {
     // Verify the server is still healthy — a proper client can still connect.
     let mut good_stream =
         UnixStream::connect(&client_socket).expect("should connect after no-hello client");
-    let (version, error) = client_handshake(&mut good_stream, 4, 80, 24)
+    let (version, error) = client_handshake(&mut good_stream, 5, 80, 24)
         .expect("proper handshake should still work after no-hello client");
-    assert_eq!(version, 4);
+    assert_eq!(version, 5);
     assert!(error.is_none());
 
     // API should still work.
diff --git a/tests/support/mod.rs b/tests/support/mod.rs
index cc1fb67b..62b63c9e 100644
--- a/tests/support/mod.rs
+++ b/tests/support/mod.rs
@@ -220,7 +220,9 @@ pub fn client_handshake(
             &encode_varint_u32(version),
             &encode_varint_u16(cols),
             &encode_varint_u16(rows),
-            &encode_varint_u32(0), // RenderEncoding::SemanticFrame
+            &encode_varint_u32(8),  // cell_width_px
+            &encode_varint_u32(16), // cell_height_px
+            &encode_varint_u32(0),  // RenderEncoding::SemanticFrame
         ],
     );
     let framed = frame_message(&hello_payload);
diff --git a/website/latest.json b/website/latest.json
index 4fe29410..94a70099 100644
--- a/website/latest.json
+++ b/website/latest.json
@@ -1,6 +1,6 @@
 {
   "version": "0.5.8",
-  "protocol": 4,
+  "protocol": 5,
   "notes": "### Added\n- Added manual pane labels through `herdr pane rename`, the `pane.rename` socket API, an optional `keys.rename_pane` binding, and the right-click pane menu.\n- Added `ui.show_agent_labels_on_pane_borders`, which can show detected or reported agent names in split pane borders when no manual pane label is set.\n- Added `herdr integration status [--outdated-only]` so installed agent integrations can be checked for legacy or outdated versions.\n- Added an optional `keys.open_notification_target` binding for jumping to the pane behind the current notification.\n- Added optional `keys.previous_agent` and `keys.next_agent` bindings for cycling through sidebar agent entries.\n\n### Changed\n- Scrolling over the tab bar now switches tabs directly, including overflowing tab bars.\n\n### Fixed\n- Indexed terminal palette colors now render correctly for 256-color terminal apps.\n- Hook-based agent integrations now reject stale out-of-order reports and base notifications on effective agent state, reducing duplicate or stuck state changes.\n- Background tabs now resize when the outer terminal size changes, preventing stale pane dimensions when switching back to them.\n- Client shutdown now drains queued control messages more reliably.\n- Pane cursors are now hidden while scrolled back, and omitted while the mobile switcher is open.\n- Mobile agent switcher entries now include tab context, making agents easier to identify on narrow terminals.\n- macOS foreground job detection now uses process groups, improving agent state tracking for foreground commands.\n- Remote SSH no longer fails before connecting when macOS temporary bridge socket paths exceed Unix socket length limits. (#103, thanks @moonsphere)\n- Nix-wrapped agent commands are now detected by their underlying agent entrypoint.\n- Pane renames made through the socket API now rerender immediately.",
   "assets": {
     "linux-x86_64": "https://github.com/ogulcancelik/herdr/releases/download/v0.5.8/herdr-linux-x86_64",