A Google search yields the GitHub page for Google Test. I'm finding many links around the web to https://github.com/google/googletest, which now redirects to the GitHub page. The GitHub project has an overview and a readme.md, which mostly explains how to build Google Test.
Where is the official user documentation for Google Test, or some equally useful, comprehensive documentation?
The documentation is in the GitHub repo, as .md files in the googletest/docs directory. Start with Primer.md. And then you can look at more advanced topics.
Shameless plug: Because it's annoying to go through the unrendered md files locally and use the difficult to navigate around md files on github, I publish the google test docs (https://gunslingerfry.github.io/google-test-docs) using mkdocs with a very minimal addition of an index.
