Starter Template: Unittest not working in normal Browser?

Ionic-cli version: 6.16.3
node-version: v14.17.3

I’ve created a new with ionic start as angular and blank. Without editing anything then npm run test and visiting the url with a recent chrome.

However the test never succeeds in chrome it just shows “Karma v.6.3.4 connected; test: loading;”.
Sometimes it’s simply stuck and sometimes I get a timeout on the server:

14 07 2021 13:36:13.737:INFO [Chrome 91.0.4472.114 (Linux x86_64)]: Connected on socket ni_YF62G-Qt7BquBAAAP with id manual-5322
14 07 2021 13:36:43.655:WARN [Chrome 91.0.4472.114 (Linux x86_64)]: Disconnected (0 times) Client disconnected from CONNECTED state (ping timeout)
Chrome 91.0.4472.114 (Linux x86_64) ERROR
  Disconnected Client disconnected from CONNECTED state (ping timeout)

Chrome 91.0.4472.114 (Linux x86_64) ERROR
  Disconnected Client disconnected from CONNECTED state (ping timeout)

How to get this working so I can start adding something?
(I’am trying to migrate an ionic-v3 app this old configuration is working without problems).

Increasing the timeout even more seems strange as I would expect the empty test to run in just a few ms otherwise it will be somewhat useless.

P.s. What seems to work is headless chrome but that can’t be a permanent solution if I wan’t to debug anything.