This happens for example if we access "/dbp-signature.html" in which case the
router interprets the file name as a language.

It always seems like the button is missing when loading the page and
expecting the button there based on experience.

Reset value attribute to really make sure it is empty and will trigger a change event when it is set again with the previous value

Register the activity properly and create a scoped element if the API is there.

One all bugs are fixed upstream this should allow us to switch to lit v2
without any further changes.

In newer versions there is now a normal method for this which also supports
dynamically added components.

The static version is deprecated and removed in 2.0, so we need to port here.

Include the highlight.js css in all activities and move the
code css into the app, so it's defined where it is used.

This has proper support for rollup while providing the same API.

This is what open-wc recommends now and uses in their @open-wc/testing package