Breaking: #72293 - API change in ExceptionHandlerInterface 

See forge#72293

Description 

The class \Throwable was added in PHP7 as new parent of \Exceptions. So we were in need to remove the type hint in forge#72117, which we now read as \Throwable instead of \Exception as we only support PHP 7.0 or newer. See https://php.net/manual/en/migration70.incompatible.php

Impact 

A fatal error will be thrown if you use own ExceptionHandlers implementing TYPO3\CMS\Core\Error\ExceptionHandlerInterface "Fatal error: Declaration of ... must be compatible with ..."

Affected Installations 

Installations which use an own ExceptionHandler implementing TYPO3s ExceptionHandlerInterface.

Migration 

Add \Throwable as type hinting in your implementation of ExceptionHandlerInterface. Check the API/type hinting of the method where you process the exception.