Deprecation: #107057 - Deprecate auto-render assets sections 

See forge#107057

Description 

The auto-rendering of template sections HeaderAssets and FooterAssets available in Fluid templates has been marked as deprecated in TYPO3 v14.0 and will be removed in TYPO3 v15.0.

Impact 

Using the deprecated sections will raise a deprecation level log error and will stop working in TYPO3 v15.0.

Affected installations 

TYPO3 installations using the sections HeaderAssets and FooterAssets in Fluid templates.

Migration 

It is recommended to use the f:asset.script or f:asset.css ViewHelpers from the TYPO3 Asset Collector API to render required assets.

In scenarios, where the f:asset.script or f:asset.css ViewHelpers are not suitable, users can use the f:page.headerData or f:page.footerData ViewHelpers to render custom HTML header or footer markup.