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Transformation Overview

The transformation of the content can be configured by listing which transformation filters to pass it through. The order of the list is the order in which the transformations are performed when saved to the database. The order is reversed when the content is loaded into the RTE again.

Processing can also be overwritten by Page TSconfig, see the according section of the Page TSconfig reference for details.

Transformation Filters


RTE Transformation filter

Transforms the HTML markup either for display in the rich-text editor or for saving in the database. The name "css_transform" is historical; earlier TYPO3 versions had a long since removed "ts_transform" mode, which basically only saved a minimum amount of HTML in the database and produced a lot of nowadays outdated markup like <font> tag style rendering in the frontend.


RTE Transformation filter

Processes anchor tags and resolves them via \TYPO3\CMS\Core\LinkHandling\LinkService before saving them to the database, while using the TYPO3-internal t3:// syntax.

In addition, it is possible to define custom transformations can be created allowing your to add your own tailor made transformations with a PHP class where you can program how content is processed to and from the database.