If you want to get stuck, use it

When I activate the Testing Environment, my page layout came to a complete mess, lots of things going on, and it does not shows a thing that it’s just the test env. After a while, I’ve had to come to my hosting account, trough the file manager to discover how to force leave this sh*ty test thing. To leave it, clear the cache on your browser that has the informations of your website, then you will be able to login again and uninstall this plugin for good.