Feature: #74109 - Set the alternative Backend Logo via Extension Manager

See forge#74109


The Backend Logo in the upper left corner can now be configured in the Extension Configuration of EXT:backend within the Extension Manager. A relative path to the TYPO3 installation ("PATH_site"), e.g. "fileadmin/myfile.jpg" or a path to an extension, e.g. "EXT:my_theme/Resources/Public/Icons/Logo.png" can be configured there.

The configuration option within the Backend extension (EXT:backend) is called backendLogo.


The previously available $GLOBALS[TBE_STYLES][logo] option has no effect anymore.