Feature: #56236 - Multiple HTTP headers of the same type in Frontend Output

See forge#56236


It is now possible to use config.additionalHeaders as a TypoScript array object to add multiple headers at the same time


config.additionalHeaders {
        10 {
                # the header string
                header = WWW-Authenticate: Negotiate

                # replace previous headers with the same name
    # optional, default is "on"
                replace = 0

                # optional, force the HTTP response code
                httpResponseCode = 401
        # always set cache headers to private, overwriting the sophisticated TYPO3 option
        20.header = Cache-control: Private

See also: https://php.net/header


The previous option config.additionalHeaders = X-Header: ABC|X-Header2: DEF is deprecated in favor of the more flexible solution.