Breaking: #110027 - StandardContentPreviewRenderer streamlined 

See forge#110027

Description 

\TYPO3\CMS\Backend\Preview\StandardContentPreviewRenderer has been turned into a stateless, dependency-injected service. It is now declared final and can no longer be subclassed. The lazy initialize() workaround that resolved its dependencies through \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance() on first use has been removed, and all dependencies are passed through the constructor instead.

Impact 

Custom preview renderers extending \TYPO3\CMS\Backend\Preview\StandardContentPreviewRenderer raise a fatal error, as the class is now final.

Affected installations 

Instances with third-party extensions that subclass StandardContentPreviewRenderer or instantiate it manually.

Migration 

Instead of subclassing StandardContentPreviewRenderer, implement \TYPO3\CMS\Backend\Preview\PreviewRendererInterface directly. The standard renderer may be composed and its rendering methods delegated to where its output is desired, as \TYPO3\CMS\Form\Preview\FormPagePreviewRenderer demonstrates.