The site only rebranded to Eating Disorder Support Forum within the past year or two. For the first decade of its existence, it was known as MyProAna. They rebranded after the original owner sold the site and the new owner forced them to change their name because they thought it was a bad business move to be seen facilitating a pro-ED forum.
The people on there say they're not actively encouraging or triggering people with EDs to get worse but you'll find countless threads of people giving each other tips on how to eat less, how to purge, how to hide their ED from their family, how to fake a higher weight for doctor's appointments, how to manipulate blood test results, etc. etc. Not to mention all the skelly bodycheck threads, "let's all get down to this weight together" threads, and a dedicated thinspo section which is 50% kpop girls because Korean beauty standards require them to be very thin.