Warning: Invalid argument supplied for foreach()

[may17]

Wortlaut der Fehlermeldung

Warning: Invalid argument supplied for foreach() in system/modules/core/widgets/MetaWizard.php on line 72

#0 system/modules/core/widgets/MetaWizard.php(72): __error(2, 'Invalid argumen...', '/www/htdocs/w00...', 72, Array)
#1 system/modules/core/library/Contao/Widget.php(804): Contao\MetaWizard->validator(NULL)
#2 system/modules/core/classes/DataContainer.php(323): Contao\Widget->validate()
#3 system/modules/core/drivers/DC_Folder.php(1210): Contao\DataContainer->row()
#4 system/modules/core/classes/Backend.php(650): Contao\DC_Folder->edit()
#5 system/modules/core/controllers/BackendMain.php(131): Contao\Backend->getBackendModule('files')
#6 contao/main.php(20): Contao\BackendMain->run()
#7 {main}

Versionen/Zusatzinformationen

• Contao: 3.5.24
• PHP: 7.0
• Browser (bei Javascript Fehlern):

Ort

• [x] Backend
• [ ] Frontend
• [ ] Contao Manager
• [ ] Composer

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