To test platform potential specific code of e.g. the WebCrypto API
Testing on Windows would be nice too, but all browsers fail to fetch resources
from the web-test-runner server.
To have tests work Browserstack Safari (also below iOS 15), as the tests are run in an iframe,
rewriting localhost as hostname, making WebCrypto not available.
We keep HTTP for the non-browserstack tests so that in local testing,
generating self-signed certs is not required.