system blueprints not getting scanned. Fixes #3296

CHANGELOG.md

@@ -11,6 +11,7 @@
     * Fixed moving `Flex Page` to itself causing the page to be lost [#3227](https://github.com/getgrav/grav/issues/3227)
     * Fixed `PageStorage` from detecting files as pages
     * Fixed `UserIndex` not implementing `UserCollectionInterface`
+    * Fixed system templates not getting scanned [#3296](https://github.com/getgrav/grav/issues/3296)
 
 # v1.7.9
 ## 03/19/2021

system/src/Grav/Common/Page/Types.php

@@ -61,7 +61,7 @@ class Types implements \ArrayAccess, \Iterator, \Countable
      */
     public function init()
     {
-        if (null === $this->systemBlueprints) {
+        if (empty($this->systemBlueprints)) {
             // Register all blueprints from the blueprints stream.
             $this->systemBlueprints = $this->findBlueprints('blueprints://pages');
             foreach ($this->systemBlueprints as $type => $blueprint) {