Add backend module to validate links on the page

composer.json

@@ -43,6 +43,7 @@
   ],
   "require": {
     "typo3/cms": "^8.7",
+    "typo3/cms-linkvalidator": "*",
     "helhum/typo3-console": "4.9.2",
     "dmitryd/typo3-realurl": "2.3.0",
     "t3o/t3olayout": "^2.1",