diff --git a/src/browser/Terminal.ts b/src/browser/Terminal.ts
index 9452833e..1c65559a 100644
--- a/src/browser/Terminal.ts
+++ b/src/browser/Terminal.ts
@@ -160,11 +160,13 @@ export class Terminal extends CoreTerminal implements ITerminal {
   }
 
   private _changeAnsiColor(event: IAnsiColorChangeEvent): void {
+    if (!this._colorManager) { return; }
+
     const color = rgba.toColor(event.red, event.green, event.blue);
 
-    this._colorManager!.colors.ansi[event.colorIndex] = color;
-    this._renderService?.setColors(this._colorManager!.colors);
-    this.viewport?.onThemeChange(this._colorManager!.colors);
+    this._colorManager.colors.ansi[event.colorIndex] = color;
+    this._renderService?.setColors(this._colorManager.colors);
+    this.viewport?.onThemeChange(this._colorManager.colors);
   }
 
   public dispose(): void {