[BUGFIX] Load correct cType list in item proc hook

If two fields of type content exist, always the first one was selected
for the cType list regardless of the parent table they belong to.

There is no optimal way right now to figure out the parent table, so the
creation string which contains the parent table is parsed.

Fixes: #382

Classes/ItemsProcFuncs/CTypeList.php

@@ -75,8 +75,15 @@ public function itemsProcFunc(&$params): void
                 }
             }
 
+            $dataString = $GLOBALS['TYPO3_REQUEST']->getParsedBody()['ajax'][0] ?? '';
+            if (preg_match_all('/tx_mask_\w+/', $dataString, $pregResult) && count($pregResult[0]) > 1) {
+                // Get the second last entry
+                $table = $pregResult[0][count($pregResult[0]) - 2];
+            } else {
+                $table = $this->fieldHelper->getFieldType($fieldKey);
+            }
+
             // load the json configuration of this field
-            $table = $this->fieldHelper->getFieldType($fieldKey);
             $fieldConfiguration = $this->storageRepository->loadField($table, $fieldKey);
 
             // if there is a restriction of cTypes specified