Breaking: #96604 - Removed ModuleTemplate->addJavaScriptCode()

See Issue #96604

Description

The backend module related class method \TYPO3\CMS\Backend\Template\ModuleTemplate->addJavaScriptCode() has been removed.

The method allowed to add JavaScript inline code to the document body of backend modules. This collides with Content-Security-Policy HTTP headers and needs to be avoided.

The method has been marked @internal in late TYPO3 v11 development and has been removed in v12.

Impact

Calling the method in an instance triggers a fatal PHP error.

Affected Installations

The extension scanner finds usage candidates as weak match. In general, instances with extensions that come with own backend modules may be affected.

Migration

There are various ways to migrate away from inline JavaScript in backend modules, a modern TYPO3 v12 solution is JavaScript ES6 modules.