Configuration

EXT:sync_crop_areas itself does not need any configuration, but it needs a configured crop column in TCA of table sys_file_reference. Usually you should have a file Configuration/TCA/Overrides/sys_file_reference.php in your SitePackage where CropVariants are defined. Of cource you also can build up the CropVariants with PageTSConfig.

$GLOBALS['TCA']['sys_file_reference']['columns']['crop']['config']['cropVariants'] = [
    'desktop' => [
        'title' => 'Desktop',
        'allowedAspectRatios' => [
            '4:3' => [
                'title' => '4/3',
                'value' => 4 / 3
            ],
            'NaN' => [
                'title' => 'Free',
                'value' => 0.0
            ],
        ],
    ],
    'mobile' => [
        'title' => 'Mobile',
        'allowedAspectRatios' => [
            '4:3' => [
                'title' => '4/3',
                'value' => 4 / 3
            ],
            'NaN' => [
                'title' => 'Free',
                'value' => 0.0
            ],
        ],
    ],
];

Attention

EXT:sync_crop_areas will only sync values of CropVariants with same ratio. In example above 4:3 exists in both CropVariants so syncing these CropVariants will not be a problem.

Usually a TCA reference to sys_file_reference in your extension should look like:

'images' => [
    'exclude' => true,
    'label' => 'LLL:EXT:glossary2/Resources/Private/Language/locallang_db.xlf:tx_glossary2_domain_model_glossary.images',
    'config' => \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::getFileFieldTCAConfig(
        'images',
        [
            ...
            'overrideChildTca' => [
                'types' => [
                    '0' => [
                        'showitem' => '
                        --palette--;;imageoverlayPalette,
                        --palette--;;filePalette'
                    ],
                    \TYPO3\CMS\Core\Resource\File::FILETYPE_TEXT => [
                        'showitem' => '
                        --palette--;;imageoverlayPalette,
                        --palette--;;filePalette'
                    ],
                    ...
                ],
            ],
        ],
        $GLOBALS['TYPO3_CONF_VARS']['SYS']['mediafile_ext']
    )
]

Attention

If you or the used extension does not make use of the palette imageoverlayPalette please have a look into section sync_crop_areas does not work for column of extension XY.