505 error is on your end. I remember @CloudFlare replying to someone around the start of the year asking what browser the guy was using to receive a 505 error. I can only assume it's the browser since it's neither a redirect or a server problem (that I know of). The "other site" you speak of is possibly CloudFlare if you see the logo up at the top while it is still under
https://forum.nostalrius.org/ or
https://cloudflare.comMicroshaft tryna outdate sites though. I'd recommend Firefox.