Apologies if the interface is not clear on that. You don't need to have an API token to use it. The field to provide an API token is only for people who otherwise have an API account and, e.g., want to use the extension for work purposes. If you don't have one, you can leave the field empty and use the extension completely for free, with the temporary exception of a small number of websites where there’s a lot of abuse (on the order of $200/300 per month in server costs).
