Breaking: #108114 - Global frontend content link prefixing removed 

See forge#108114

Description 

The frontend rendering contained logic that searched for links to resources within the generated Response content to globally replace them with the configured URL prefix (TypoScript config.absRefPrefix).

This solution has always been brittle and has now been obsoleted with the introduction of the System Resource API.

The global search and replace code has been removed, which also obsoletes setting $GLOBALS['TYPO3_CONF_VARS']['FE']['additionalAbsRefPrefixDirectories'] .

Impact 

Generated content can no longer expect links to resources to be globally "fixed". They must create the final URL themselves.

The obsolete $GLOBALS['TYPO3_CONF_VARS']['FE']['additionalAbsRefPrefixDirectories'] will be automatically removed from settings.php after upgrading to TYPO3 v14 and accessing the install tool.

Affected installations 

The System Resource API is integrated into TYPO3 in a way that extensions usually create proper links automatically as long as the provided Core API is used.

Instances with extensions that hard code link generation may be affected.

Migration 

Instances should check the rendered frontend for broken links after upgrading to TYPO3 v14 and update hard coded link generation to use proper API calls, for example based on the various URL, URI and asset-related Fluid ViewHelpers.

This change depends heavily on the specific extension code. There is no general advice that covers all possible cases for extension developers.