Unfortunately, Unreal Engine does not support web versions; you can only download them.
Viewing post in Curse of the place jam comments
Nothing personal, but I would hope you're aware that it's super easy to get malware executables to this site, and that you shouldn't trust the word of strangers on the internet, but take proper precautions. So to try out a downloadable, I'd need to set up the isolated sandbox and the virus and malware scans. I'd rather not.