In my case it was;

a:4:{i:0;s:101:"The requested component ("productvideo")
is not found. Before using, you must add the
implementation.";i:1;s:9220:"#0
/var/www/detintelligentehjem.dk/public_html/vendor/magento/module-ui/Model/Manager.php(207):
MagentoFrameworkViewElementUiComponentConfigProviderComponentDefinition->getComponentData('productvideo')

The problem was a extension in the Magento 1.9.2.4 I
imported the data from. That caused this problem. I solved it
by deleting productvideo from eav_attribute in the
database.