diff --git a/composer.json b/composer.json
index 4a49d95..39acb49 100644
--- a/composer.json
+++ b/composer.json
@@ -2,6 +2,6 @@
     "minimum-stability": "dev",
     "prefer-stable": true,
     "require": {
-        "felixfbecker/language-server": "^2.3.0"
+        "felixfbecker/language-server": "^3.0.0"
     }
 }
diff --git a/src/extension.ts b/src/extension.ts
index 5801453..f40b20c 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -74,8 +74,7 @@ export async function activate(context: vscode.ExtensionContext): Promise<void>
             });
             // Listen on random port
             server.listen(0, '127.0.0.1', () => {
-                const address = '127.0.0.1:' + server.address().port;
-                spawnServer('--tcp', address);
+                spawnServer('--tcp=127.0.0.1:' + server.address().port);
             });
         } else {
             // Use STDIO on Linux / Mac