python -m http.server leads to a SecurityError due to bad content types

[aokasumi]

Using python -m http.server 8001 with Python 3.7 on Windows 10 to start a simple server as described will result in the following message printed on to the console in Firefox 74.0:
Registration failed with SecurityError: The operation is insecure.

Using Chrome, you can get the following additional information:
Registration failed with SecurityError: Failed to register a ServiceWorker for scope ('http://localhost:8001/sw-test/') with script ('http://localhost:8001/sw-test/sw.js'): The script has an unsupported MIME type ('text/plain').

It seems like the Python http.server module is unable to use the correct mimetypes in the HTTP response for JavaScript files. Also, the content types of the other JavaScript files are text/plain as well in the HTTP response, as for example in the response of app.js:

HTTP/1.0 200 OK
Server: SimpleHTTP/0.6 Python/3.7.4
Date: Thu, 19 Mar 2020 19:27:39 GMT
Content-type: text/plain
Content-Length: 2143
Last-Modified: Thu, 19 Mar 2020 19:24:15 GMT

The content types of the JPEG images seem to be okay.

If you experience the same problem, starting a server using the Python script at https://gist.github.com/HaiyangXu/ec88cbdce3cdbac7b8d5 works for me.

[qiufeihong2018]

Can you use 'python -m SimpleHTTPServer 8001'? @aokasumi