diff --git a/lib/Server.js b/lib/Server.js
index de00af8208..611f0c2045 100644
--- a/lib/Server.js
+++ b/lib/Server.js
@@ -155,6 +155,10 @@ class Server {
       }
 
       this.sockWrite(this.sockets, 'progress-update', { percent, msg });
+
+      if (this.listeningApp) {
+        this.listeningApp.emit('progress-update', { percent, msg });
+      }
     }).apply(this.compiler);
   }
 
diff --git a/lib/servers/WebsocketServer.js b/lib/servers/WebsocketServer.js
index 34002c675a..3021f40341 100644
--- a/lib/servers/WebsocketServer.js
+++ b/lib/servers/WebsocketServer.js
@@ -31,11 +31,13 @@ module.exports = class WebsocketServer extends BaseServer {
     const noop = () => {};
 
     setInterval(() => {
-      this.wsServer.clients.forEach((ws) => {
-        if (ws.isAlive === false) return ws.terminate();
+      this.wsServer.clients.forEach((socket) => {
+        if (socket.isAlive === false) {
+          return socket.terminate();
+        }
 
-        ws.isAlive = false;
-        ws.ping(noop);
+        socket.isAlive = false;
+        socket.ping(noop);
       });
     }, this.server.heartbeatInterval);
   }
diff --git a/test/server/progress-option.test.js b/test/server/progress-option.test.js
index 1d0a858ae9..ad2369303a 100644
--- a/test/server/progress-option.test.js
+++ b/test/server/progress-option.test.js
@@ -46,7 +46,13 @@ describe('progress', () => {
       });
 
       compiler.run(() => {});
-      server.listen(port, 'localhost');
+      const app = server.listen(port, 'localhost');
+
+      app.on('progress-update', ({ percent, msg }) => {
+        expect(percent).toBeGreaterThanOrEqual(0);
+        expect(percent).toBeLessThanOrEqual(100);
+        expect(typeof msg).toEqual('string');
+      });
     });
   });
 });