web-test-runner crashes in debug mode

[cdaringe]

Problem

Using yarn test -- --open --manual, then proceeding to debug tests results in silent failure. For example:

[snowpack] File changed...
[@snowpack/plugin-typescript] 7:47:52 PM - File change detected. Starting incremental compilation...
[@snowpack/plugin-typescript] 7:47:52 PM - Found 0 errors. Watching for file changes.
Debug manually in a browser not controlled by the test runner.
 
Advanced functionalities such commands for changing viewport and screenshots don't work there.
Use the regular debug option to debug in a controlled browser.
 
Local address:   http://localhost:9556/
Network address: http://192.168.0.9:9556/
 
Press D to open the browser.
Press Q to exit manual debug. # go about using chrome, debugging your test, then ...
error Command failed with exit code 1. # this message occurs, perhaps unknown to you, as you're studying your tests!

Repro

• npx create-snowpack-app new-dir --template @snowpack/app-template-preact-typescript --use-yarn
• yarn test -- --open --manual
• open chrome, open debugger
• interactively debug the test with breakpoints, refreshing the page time-to-time

[LarsDenBakker]

I'm not able to reproduce this issue. Could you explain more about the steps you're taking in the browser before it crashes? And how does the crash manifest? Is it the browser? Are there any errors logged to the terminal.