Important: #104839 - RTE processing YAML configuration now respects `removeTags`

Description

Important

Short version: With this bugfix, any save process to the contents of an existing RTE element will now properly apply the removeTags default configuration (unless configured otherwise).

To prevent a breaking change, the tags center, font, strike and u are now allowed to be saved by default (like it was with the bug in effect). This is planned to be changed with TYPO3 v14 as a breaking change.

The unexpected tags link, meta, o:p, sdfield, style, title will now be removed.

This behaviour can always be customized by setting removeTags appropriately.

TYPO3 allows to configure which HTML tags are allowed to be persisted to the database in case of Richtext-elements. This can be configured either within the CKEditor YAML context, or via Page TSconfig:

EXT:rte_ckeditor/Configuration/RTE/Processing.yaml

processing:
  HTMLparser_db:
    # previous default: center, font, link, meta, o:p, sdfield,
    #                   style, title, strike, u
    removeTags: [link, meta, o:p, sdfield, style, title]

EXT:my_extension/Configuration/TypoScript/page.tsconfig

RTE.default.proc {
  HTMLparser_db {
    removeTags = link, meta, o:p, sdfield, style, title
  }
}

Due to a bug in interpreting the YAML configuration, the syntax using an array was actually never in effect.

This means, any implementation relying on such a YAML configuration (without providing Page TSconfig), would not have removed the listed tags.

Due to TYPO3's internal processing, from those tags listed above, the previous default tags center, font, strike and u were persisted to the database and also later evaluated in the frontend.

The other tags link, meta, o:p, sdfield, style and title were displayed as HTML encoded entities due to other sanitizing in the output (but still stored as HTML tags in the database).

These tags will no longer be stored by default now, and is considered a non-breaking bugfix, because these tags should not occur within an RTE.

This wrong parsing has now been fixed, so that now both an array syntax as well as string syntax is allowed in the YAML processing and will be applied. Adapting the removeTags setting allows to change the now applied defaults to any tag configuration needed.

Hint

Custom YAML configuration that used a string representation of removeTags (instead of an array) was already properly evaluated.

This bugfix has not been backported to TYPO3 v11 installations, to prevent a change of behaviour in a security-maintenance-only environment. If this fix is needed, you can convert the CKEditor array syntax by removing the square brackets in a Processing.yaml override:

removeTags: [center, font, link, meta, o:p, sdfield, strike, style, title, u]

to:

removeTags: center, font, link, meta, o:p, sdfield, strike, style, title, u

Affected installations

TYPO3 setups with RTE YAML configurations utilizing either a custom removeTags processing directive or the default, defined via array notation instead of string.

Migration

Adjust the RTE YAML configuration processing directive removeTags to suit the expected tag removal, or accept the new defaults.

Important: #104839 - RTE processing YAML configuration now respects removeTags

Description

Affected installations

Migration

Important: #104839 - RTE processing YAML configuration now respects `removeTags`