Using the method setContentUrl you can set the base url of the request when using the html method. Sometimes you may have relative paths in your code. When passing a html page to puppeteer, you don't have a base url set. So any relative path present in your html content will not fetch correctly.
Browsershot::html('<html>... relative paths to fetch ...</html>')
->setContentUrl('https://www.example.com')
...
