FilterProxy::Header Config for site .*

Use the above lists to filter header records. The default is to allow all headers. The remove filters are then applied, and then the allow list. Use the remove filter to remove unwanted header records from broad host specifications, such as .*, and then use the allow list to permit exceptions to the broad remove rules. Be aware that modifying the headers in any way can break certain types of authentication that requre the HTTP response be unmodified from when it was sent from the server. (often, annoying e-commerce sites) If you find a site like this, disable the Header module for that site.

Here are some headers you may wish to consider removing:

referer	Allows the web server to see the URL of the page that linked to their site. For example, if you got to their site by doing a search on a web search engine, they will know what keywords you were searching for. If you maintain a personal web page with your bookmarks, they would get the URL for that page if you include them on it. Obviously, this field is a great invasion of privacy, and I would strongly consider filtering it for all sites. A few sites, however, don't allow you to see some of their content unless you have a referer header that shows that you are coming from their web site. This is done to prevent other sites from linking to internal content. You can get around this problem by allowing the header on a host by host basis.
user-agent	This tag tells the web site which operating system you use, and what browser version you use.
cookie set-cookie	These headers allow a site to save small bits of information on your hard drive, which they can ask for later if you return to their site. The set-cookie header allows the site to give you the information, and the cookie header is where your browser gives it back to the server. As originally intended, cookies are actually a good thing. Advertisers, however, have exploited cookies in such a way that they can use them to track your browser sessions between web sites, and join that information with other personal information about you. Don't filter cookies here if you have another module already doing so, such as FilterCookies.