As reported by @ema, Kibana short URLs (like https://logstash.wikimedia.org/goto/1934acb94b581060b6dad36f8fd0c79e) end up in an error (Kibana did not load properly. Check the server output for more information.). This looks related to GH issue 12915. The workaround proposed there is to create an empty /usr/share/kibana/optimize/bundles/stateSessionStorageRedirect.style.css file. Testing this solution on logstash1008, it does seem to fix the issue, but is incredibly ugly as a workaround.
We are running kibana 5.5.2. It is unclear if a fix is available. The GH issue reports at least 5.6.3 being also broken.