To get all output of the Chrome console call consoleMessages.
$consoleMessages = Browsershot::url('https://example.com')->consoleMessages(); // returns an array
The consoleMessages method return an array of which each item is yet another array with these keys:
type: the type of output (log, error, ...)
message: the message itself
location: an array with information on where the console message was triggered. In most cases, the url key will contain the URL where the message was triggered.