iOS 26.5 (23F77): userspace tunnel drops after connect -> WDA IDE session timeout

[hassineabd]

iPhone SE, iOS 26.5 (23F77), macOS 26, go-ios v1.2.0 (also tried v1.0.218), provider running as root.

Userspace tunnel connects, then drops ~6s later:
framedIPv6Reader: failed to read IPv6 header: read unix ->/var/run/usbmuxd: use of closed network connection
=> WDA: runXUITestWithBundleIdsXcode15Ctx: cannot initiate a IDE session: Timed out (loops).

Same device worked on iOS 26.2. v1.0.218 & v1.2.0 both fail on 26.5. Pairing OK, Developer Mode on, DDI downloads.
Looks like the userspace IPv6 framing (#748, validated on 18.4) doesn't fit iOS 26.5. Related: #771, #631.

[danielpaulus]

Keeping this open. Current working hypothesis: iOS 26.5 changed the lockdown-tunnel keepalive/framing so the device closes the connection a few seconds after establishment — which matches your "connects, then drops ~6s later" pattern and the fact that 26.2 worked with the same binary. Our farm tops out at iOS 18, so we can't reproduce this directly. What would help pin it down: a --verbose (ideally --trace) log of ios tunnel start --userspace from establishment through the drop on 26.5, on the latest release, so we can see the last frames exchanged before the device closes the connection.