[jochen-testingbot]

Version bump to 5.1, the changelog for everything merged since v5.0 (#58–#73), and a README section for --ssh-connections. There are no code changes.

Highlights (full list in CHANGELOG)

• Several SSH connections to the tunnel server (--ssh-connections, default 4). On servers that can't spread traffic over them, the client falls back to one connection on 2010. (Open several SSH connections to the tunnel server (--ssh-connections, default 4) #72)
• 2 MB forwarded-channel window: uploads are up to 10× faster at real-world latency. (Raise the forwarded-channel window from 128 KB to 2 MB (vendored JSch class) #70)
• A dead session is noticed in about 6 s instead of 15 minutes, and port 2010 survives reconnects. (Keep port 2010 working through reconnects: notice dead sessions, retry the forward, probe it #69, Notice a dead session in ~6 s instead of ~15, and reconnect sooner #71)
• PAC files:
  • the failover list is honoured (Honour the PAC failover list when a proxy cannot be reached #64);
  • isInNet resolves host names (Resolve a host name passed to isInNet, as the PAC specification does #65);
  • a bad file fails before a tunnel server is provisioned (Load --pac-local before creating the tunnel, so a bad PAC file fails fast #66).
• --noproxy port fix (Point the reverse forward at 8087 under --noproxy without --localproxy #67), readable errors for an incomplete API response (Report an incomplete API response as one, not as a stack trace #68), quieter startup (Don't log web's Squid warm-up request as a failure #73), the Windows download (Package the Windows runtime with 7-Zip, and build runtimes in PR CI #58).

Verified

• mvn verify: 1055 tests, 0 failures. It produces TestingBotTunnel-5.1-shaded.jar.
• main (d049a56) ran on a tunnel02 canary on 2026-10-27:
  • 4 of 4 SSH connections forwarding on 2020–2023;
  • tunnel-mux at 4/4 healthy forwards;
  • browser traffic passing.

To release after merging

• Tag v5.1. release.yml then builds the jar, the native runtimes, Maven Central and Docker (5.1, latest).
• Add the release notes: gh release edit v5.1 --notes-file <5.1 section of CHANGELOG>. Action-created releases come out with an empty body.
• Web: serve 5.1 as the download (public/tunnel/).