Method constructor

frontend/src/tests/qa.test.ts:449–455

(url: string)

      listeners: Record<string, Array<(event: unknown) => void>> = {};

      constructor(url: string) {
        this.url = url;
        window.setTimeout(() => {
          this.readyState = MockWebSocket.OPEN;
          this.emit("open", {});
        }, 10);
      }

      addEventListener(type: string, listener: (event: unknown) => void) {
        if (!this.listeners[type]) {