1  if (!this.browser) {
2    this.browser = await puppeteer.launch(this.OPT)
3    const pages: puppeteer.Page[] = await this.browser.pages()
4
5    // close chromium by catching 'targetdestryed'
6    this.browser.on('targetdestroyed', async () => {
7      if (this.browser) {
8        const pages: puppeteer.Page[] = await this.browser.pages()
9        if (pages.length === 0) {
10          process.exit(0)
11        }
12      }
13    })
14  }
15