Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The Window.dump() method logs messages to the browser's standard output (stdout). If the browser was started from a terminal, output sent to dump() will appear in the terminal.
Output from dump() is not sent to the browser's developer tools console. To log to the developer tools console, use console.log().