License not verifyinb behind Caddy proxy

[Halfhumanhalfvulcan]

I'm running felddy's Foundry docker on Unraid behind a Caddy reverse proxy. The caddyfile looks like this:

foundry.nottellingyoumyurl.com {
reverse proxy XXX.XXX.X.XX:3000
}

When I try to access the Foundry server I get a /license url and a screen with just the Foundry logo on it. The log for the container says [warn] Software license requires signature, and from what I can tell its a WebSockets issue, but I can't find a good answer as to why Caddy isn't handling it properly. I have the FOUNDRY_PROXY_SSL set to true and FOUNDRY_PROXY_PORT set correctly in the docker settings.