SOLVED: Traefik Reverse proxy works with https but shows "Select Server" with http

[davedv]

Additional info:

disabling STS-specific headers in the middleware doesn't help:
<code>
# - 'traefik.http.middlewares.jellyfin-mw.headers.STSSeconds=315360000'
# - 'traefik.http.middlewares.jellyfin-mw.headers.STSIncludeSubdomains=true'
# - 'traefik.http.middlewares.jellyfin-mw.headers.STSPreload=true'
# - 'traefik.http.middlewares.jellyfin-mw.headers.forceSTSHeader=true'
</code>

Relevant parts from Jellyfin's log:
<code>
[...]
jellyfin | [custom-init] No custom files found, skipping...
jellyfin | [09:24:27] [INF] [1] Main: Jellyfin version: 10.10.6
jellyfin | [09:24:27] [INF] [1] Main: Environment Variables: ["[JELLYFIN_LOG_DIR, /config/log]", "[JELLYFIN_CONFIG_DIR, /config]", "[JELLYFIN_CACHE_DIR, /config/cache]", "[JELLYFIN_DATA_DIR, /config/data]", "[JELLYFIN_WEB_DIR, /usr/share/jellyfin/web]"]
jellyfin | [09:24:27] [INF] [1] Main: Arguments: ["/usr/lib/jellyfin/bin/jellyfin.dll", "--ffmpeg=/usr/lib/jellyfin-ffmpeg/ffmpeg"]
jellyfin | [09:24:27] [INF] [1] Main: Operating system: Ubuntu 24.04.2 LTS
jellyfin | [09:24:27] [INF] [1] Main: Architecture: Arm64
jellyfin | [09:24:27] [INF] [1] Main: 64-Bit Process: True
jellyfin | [09:24:27] [INF] [1] Main: User Interactive: True
jellyfin | [09:24:27] [INF] [1] Main: Processor count: 4
jellyfin | [09:24:27] [INF] [1] Main: Program data path: /config/data
jellyfin | [09:24:27] [INF] [1] Main: Log directory path: /config/log
jellyfin | [09:24:27] [INF] [1] Main: Config directory path: /config
jellyfin | [09:24:27] [INF] [1] Main: Cache path: /config/cache
jellyfin | [09:24:27] [INF] [1] Main: Temp directory path: /tmp/jellyfin
jellyfin | [09:24:27] [INF] [1] Main: Web resources path: /usr/share/jellyfin/web
jellyfin | [09:24:27] [INF] [1] Main: Application directory: /usr/lib/jellyfin/bin/
jellyfin | [09:24:27] [INF] [1] Emby.Server.Implementations.AppBase.BaseConfigurationManager: Setting cache path: /config/cache
jellyfin | [09:24:28] [INF] [1] Emby.Server.Implementations.ApplicationHost: Loading assemblies
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Defined LAN subnets: ["127.0.0.1/8", "10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16"]
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Defined LAN exclusions: []
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Used LAN subnets: ["127.0.0.1/8", "10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16"]
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Filtered interface addresses: ["127.0.0.1", "172.18.0.3"]
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Bind Addresses ["0.0.0.0"]
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Remote IP filter is Allowlist
jellyfin | [09:24:28] [INF] [1] Jellyfin.Networking.Manager.NetworkManager: Filtered subnets: []
</code>