diff --git a/src/client.ts b/src/client.ts
index 8591d9a..88533a0 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -176,6 +176,13 @@ async function send<T>(
    Public API
 ────────────────────────── */
 
+export async function closeClient() {
+  if (!socket) return;
+  socket.close();
+  socket = null;
+  connecting = null;
+}
+
 export async function addRun(
   useLocalhost: boolean,
   problem: string,
diff --git a/src/extension.ts b/src/extension.ts
index 385b938..4a1e5c2 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -4,6 +4,7 @@ import { startServer, stopServer } from "./server";
 import os from "os";
 import { exec } from "child_process";
 import net from "net";
+import { closeClient } from "./client";
 
 var globalStatusBarItem: vscode.StatusBarItem | undefined;
 
@@ -105,6 +106,7 @@ export function activate(context: vscode.ExtensionContext) {
 
 export function deactivate() {
   stopServer(globalStatusBarItem as any);
+  closeClient();
 }
 
 export function canConnect(
diff --git a/src/move.ts b/src/move.ts
index 8b9a1a9..12db055 100644
--- a/src/move.ts
+++ b/src/move.ts
@@ -129,7 +129,7 @@ export function startMonitoring(useLocalhost: boolean, runId: string) {
           moveId: moveId++,
           changes: {
             from: 0,
-            to: serverText.length,
+            to: serverText?.length || 0,
             insert: editorText,
           },
         },