Hi everyone, I'm the author of this extension, I lost access to my old account and can't update it anymore, so I made a new account and uploaded a new version with a different name.

You can find it by the name of "Goodreads ratings in Amazon". That one is also updated so it will work with the new Amazon page design.

Sorry for the inconvenience.

Love this so much.
It saves me a great deal of time, and I use it almost every day, often multiple times a day.
Essentially, any time I ever look at a book on Amazon, it is there and saves me having to do a separate search to find the book on Goodreads.
If I want to, I can just click-through to the Goodreads page (or right click to open in a new tab).
So much convenience, and so simple!
Thank you very much Ruben, for creating and sharing this with us.