To be pedantic, the version I linked to is a paid addin. However, you are correct - there is/are unofficial unpaid and unsupported versions available that I was

To be pedantic, the version I linked to is a paid addin. However, you are correct - there is/are unofficial unpaid and unsupported versions available that I was unaware of, per the FAQ and the repository that you linked, which has nothing to do with GPGTools GmbH; from the repo, “This does not constitute any endorsement or promotion of our releases by the respective copyright or trademark holders.” Thanks for sharing this.