It has new API which we want to use.

Newest Ubuntu switched Firefox to a snap, which breaks karma.

Try to use playwright to download and cache firefox/chromium
and use those for karma.

Compared to puppeteer where we did this some time ago this caches
the browsers globally, and only downloads them when we start the tests.

This reverts commit 6324718b.

This reverts commit 3716524b.

Just change all imports and dependencies.

No longer needs babel, but requries an alpha version of the typescript plugin
for eslint 8 support

Proof of concept for text display from a separate json file,
all array items of key 'hi' are printed to the browser console.