You don't need to have an API token to use the extension. Apologies if the interface is not clear on that. 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).

Really sorry about the experience with audio recording! We’ve now fixed the issues & bugs related to it!

Starting with version 3.2.4 (it's live now! you can update the extension in Extensions -> Settings -> Check for Updates), audio should not be muted on any websites, and audio recording should work perfectly almost everywhere, including basically all video players.

(Thanks for taking the time to write the review! It marginally prompted us to actually spend effort figuring out the issue, getting help from the community, and finally fixing it. That took hundreds of lines of fairly complicated code.)