Large transfer stalls at 100% and wipes transferred data on interruption

I tried transferring a large folder structure with magic-wormhole between a Mac and Linux laptop connected to the same (public) Wi-Fi network. The transfer reaches 100% in about half an hour but then freezes. The sender says it's waiting for confirmation while the receiver displays the loading bar at 100%. I stays like this for at least another half hour. Ctrl-C on the receiver cleanly quits on the receiver and raises twisted.internet.error.ConnectionClosed on the sender. Afterwards not a single transferred file can be found on the receiver. It's an extremely frustrating failure mode.

I am not sure how I can help reproduce this beyond listing the information below. I am happy to run a debug build of some kind if that is possible.

Software

wormhole --version gives magic-wormhole 0.24.0 on both computers. Not sure what Python version Wormhole is running under or if that is even relevant.

Sender hardware

OS: Sonoma 14.0 (23A344) CPU: 2.6 GHz 6-core Intel Core i7 Disk: APFS, 6.59 GB free space

Receiver hardware

OS: Linux Mint 22.3 64-bit CPU: 1.6 GHz 4-core Intel Core i5-8250U Disk: ext4, 1.3 TB free space Kernel: 6.17.0-35-generic

Payload

31.53 GB 10 633 "items", whatever Mac Finder means by that...

Environment variables

Both computers have these exact variables.

WORMHOLE_ACCEPT_FILE=1
WORMHOLE_QR=0