Chromium fails to start as root — `Failed to connect to browser` (need `no_sandbox=True`)

[fttomas]

When running ghcr.io/imputnet/yt-session-generator:webserver inside Docker (in turn inside an unprivileged Proxmox LXC, but the same likely applies in any rootless/sandboxed environment), the internal Chromium instance fails to start, and /get_pot returns 404 indefinitely.

Logs

[INFO] internally launching GUI (X11 environment)
[INFO] starting Xvfb
[INFO] launching chromium instance
[extractor] [INFO] update started
[extractor] [WARNING] update failed: timeout waiting for outgoing API request

Failed to connect to browser
---------------------
One of the causes could be when you are running as root.
In that case you need to pass no_sandbox=True
---------------------

The container runs as root by design (per README), and the launcher (pyppeteer/nodriver) does not pass no_sandbox=True, so Chromium's sandbox refuses to start.

Reproduce

• Pull ghcr.io/imputnet/yt-session-generator:webserver
• Run inside Docker inside an unprivileged Proxmox LXC (PVE 8.x, Debian 13, Docker 29.4.3, nesting=1, keyctl=1, no extra capabilities)
• docker logs yt-session-generator shows the messages above
• Downstream effect on cobalt: POST /get_pot returns 404 Not Found, which causes cobalt to log Failed loading poToken & visitor_data every 5 minutes and fail YouTube tunnels with empty payloads.

Environment

• Image: ghcr.io/imputnet/yt-session-generator:webserver
• Embedded Chromium: 124.0.6367.78 (Alpine)
• Host: Proxmox VE, unprivileged LXC, Debian 13 (trixie)
• Docker: 29.4.3
• cobalt: ghcr.io/imputnet/cobalt:11 (v11.7.1)

Suggested fix

Pass no_sandbox=True to the browser launch arguments (or equivalent --no-sandbox Chromium flag) — since the container is intentionally rooted, sandbox cannot work anyway.