"Not found" when I try to access cockpit behind nginx

[denbkh]

version: 333-1~bpo24.04.1
Relevant part of nginx conf:

    location /cockpit-baseUrl/ {
        # WebSocket support
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        # Proxy the request to the backend server
        proxy_pass http://127.0.0.1:9090/;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

cockpit conf:

$ cat /etc/cockpit/cockpit.conf
[WebService]
ProtocolHeader = X-Forwarded-Proto
ForwardedForHeader = X-Forwarded-For
UrlRoot = /cockpit-baseUrl/

After each request I see this error in journal:
cockpit-ws[17612]: g_hash_table_lookup: assertion 'hash_table != NULL' failed

Very helpful message (sarcasm):

[denbkh]

fixed by removing slash (kudos to Google Gemini AI)
proxy_pass http://127.0.0.1:9090;

[denbkh]

see how the error message should be displayed: