These are websites hosted on GitHub that act as a middleman between you and the internet. When you type "Roblox.com" into the proxy, the GitHub site fetches the data and displays it for you. To the school network, it just looks like you are visiting a GitHub coding repository.
Robloxunblockedgithubio and similar sites may seem appealing, but it's essential to prioritize caution and consider the potential risks. Instead of using unblocked sites, explore official channels and alternatives to access Roblox content safely and securely. If you do choose to use such sites, be aware of the potential risks and take necessary precautions to protect your device and account. robloxunblockedgithubio