Hi 77ideas 👋 Great to hear you'd like to know more about Buttonizer and it's TOS 🙂
The third party you're talking about is Freemius. We are using Freemius for managing our licenses so we can focus on building a great plugin instead of an advanced licensing system (and maintain that).
Freemius handles the payments, subscriptions and license codes and we can see and manage these data. The Freemius API will give your website a public and private API key to communicate with the Freemius API to check the licensing. If you decide to share data we can see if you have Buttonizer installed, what version you have installed and if it's a premium license or not.
The reviewers you mentioned are talking about the TOS of the website of Freemius. They claimed Freemius and our plugin was 'allowed to inject links into their website'. But that is not the case in any way and is not even allowed by the WordPress plugin guidelines.
What happens when I do not allow sharing data?
When you disallow sharing data you can use the free version of Buttonizer forever (updates included), there will be no data sent to Freemius. But, it will not be possible upgrade to our premium version or enter a license key during that perod as it's not possible to check the license key on the license servers.
Beside that, if you're not planning to upgrade Buttonizer (or not yet), you can continue using Buttonizer without sharing data. There will be no problems!
It is possible to enable sharing data later on and upgrade to Buttonizer Premium.
Account
If you did install Buttonizer earlier and you allowed sharing data (or you have a license key activated), you can login with the attached email address on our account page or via Freemius to see what data they (and we) know from you.
You can login into your account at Freemius with your email address that you use on your WordPress instance: https://users.freemius.com/ or via our page https://buttonizer.pro/account (that links to the same page and shows the same information).
Does Freemius share data?
No, according to their TOS and their FAQ they claim not to share the data with third parties. Also, we do pay for the service, so we also expect from them they do not share any data to other third parties.
Questions
If you have any additional questions about this relationship with Freemius I'd love to answer them. I'll also write a knowledge base article about Freemius where we will explain more about how we use it for our licensing!