As described in this post Firefox allows you to take a screenshot from the console with the command: :screenshot.

I would like to automate this (resize the window and take a screenshot each time) with JavaScript to show off a responsive website.

This is my attempt:

setTimeout(() => {

   eval(':screenshot');

}, 500);

When i execute it from the console it gives me the following error:

Uncaught SyntaxError: expected expression, got ':'

I feel that this is expected. However, I would like to find a way to execute these browser specific commands with JavaScript. Is that possible? Solutions for any other browser are also welcome. Thanks in advance!

Edit: This question is similar, but I am not trying to create an extension and there is no user. I want to run the script from the console myself. Just added it to make sure my question does not get flagged as a duplicate.