Breaking: #97550 - TypoScript option config.disableCharsetHeader removed

See forge#97550

Description

The TypoScript flag config.disableCharsetHeader has been completely removed from TYPO3 Core.

This option was used to avoid sending HTTP headers of type Content-Type to the client. This flag was mainly used to overcome a technical limitation to override the Content-Type information back in TYPO3 v4.x.

Impact

TYPO3 now always sends the Content-Type header to the client in the TYPO3 Frontend.

Affected installations

TYPO3 installations having this option enabled via TypoScript.

Migration

It is not needed to set this option. Even when Extbase plugins return JSON-based Responses, the Content-Type header is already modified.

In special cases, when custom headers are required, it is possible to modify the headers via a PHP-based PSR-15 middleware, or via TypoScript with "config.additionalHeaders".