Fixed Flex Pages allowing root page to be deleted

CHANGELOG.md

@@ -4,6 +4,7 @@
 1. [](#bugfix)
     * Regression: Flex not working in PHP 7.2 or older
     * Fixed creating first user from admin not clearing Flex User directory cache
+    * Fixed Flex Pages allowing root page to be deleted
 
 # v1.7.0-rc.4
 ## 02/03/2020

system/src/Grav/Framework/Flex/Pages/Traits/PageAuthorsTrait.php

@@ -123,6 +123,11 @@ trait PageAuthorsTrait
      */
     protected function isAuthorizedOverride(UserInterface $user, string $action, string $scope, bool $isMe): ?bool
     {
+        if ($action === 'delete' && $this->root()) {
+            // Do not allow deleting root.
+            return false;
+        }
+
         $isAuthor = !$isMe || $user->authorized ? $this->hasAuthor($user->username) : false;
 
         return $this->isAuthorizedByGroup($user, $action, $scope, $isMe, $isAuthor) ?? parent::isAuthorizedOverride($user, $action, $scope, $isMe);