OpenID Connect Auth Immediately Redirects to /null

I've tried many times following some of the configurations above, but for some strange reason, keep getting redirected to http://ZEPPELIN_ROOT/null. It appears that a request for http://ZEPPELIN_ROOT/api/security/ticket is denied ("401 unauthorized request") and subsequently redirected to{{/null}} (It does this very quickly). Strangely enough, however, I can manually access http://ZEPPELIN_ROOT/api/security/ticket, login, and then once I manually navigate to http://ZEPPELIN_ROOT it shows I'm logged in.

I can pass the test in the buji-pac4j-demo project through shiro.ini, I'm not sure what the fix should be, but it looks like this is definitely a Zeppelin issue, not a pac4j one.