There should be no differences between protocol-http and protocol-httpclient whether the HTTP header fields Accept, Accept-Language and Accept-Charset are configurable. The configured values should be used for both plugins. In addition,
- it should be possible to unset the default values (overwrite with empty value) so that no HTTP header field is sent
- default values should be contained in nutch-default.xml
Note: Accept-Encoding should not be configurable as the protocol plugins must support the accepted compression codecs which may not be the case e.g. for Brotli.