In the test output, there are lots of tracebacks like this one:

    "./software/caddy-frontend/test/test.py", line 534, in do_GET
        for header in config.pop('X-Drop-Header', '').split():
    AttributeError: 'NoneType' object has no attribute 'split'

this does not seem to impact the test result, but it makes the result hard to
read.