OK. It seems to be a region specific problem.
I’m accessing from Japan but tried to load the page from Singapore and US west but they loaded like normal.
For me, the initial page load takes quite literally over a minute and then pretty much times out and then on second or third try, it loads after a while using the previously fetched cache.
This is the application.js but the TTFB alone is quite crazy.
You might want to consult the Hetzner support if their network is acting nuts for some regions or put it over Cloudflare, so everyone gets it from region edge servers.