This test examines whether the domains used by Meek (a type of Tor bridge) work in tested networks.
Meek is a pluggable transport which uses non-blocked domains, such as google.com, awsstatic.com (Amazon cloud infrastructure) and ajax.aspnetcdn.com (Microsoft azure cloud infrastructure), to proxy its users over Tor to blocked websites, while hiding both the fact that they are connecting to such websites and how they are connecting to them. As such, Meek is useful for not only connecting to websites that are blocked, but for also hiding which websites you are connecting to.
Below is a simplified explanation of how this works:
[user] → https://www.google.com] → Meek hosted on the cloud] → Tor] → blocked- [website]
The user will receive a response (access to a blocked website, for example) from cloud-fronted domains, such as google.com, through the following way:
[blocked-website] → Tor] → Meek hosted on the cloud] → https://www.google.com] → [user]
In short, this test does an encrypted connection to cloud-fronted domains over HTTPS and examines whether it can connect to them or not. As such, this test enables users to check whether Meek enables the circumvention of censorship in an automated way.