[5.1] Load Schema.org only in proper forms

plugins/system/schemaorg/src/Extension/Schemaorg.php

@@ -531,6 +531,10 @@ protected function isSupported($context)
         $parts     = explode('.', $context, 2);
         $component = $this->getApplication()->bootComponent($parts[0]);
 
-        return $component instanceof SchemaorgServiceInterface;
+        if ($component instanceof SchemaorgServiceInterface) {
+            return \in_array($context, array_keys($component->getSchemaorgContexts()));
+        }
+
+        return false;
     }
 }