From 5d16d55949ead2fc689af4fd0fa058a706b9e263 Mon Sep 17 00:00:00 2001
From: "Eloy Lafuente (stronk7)" <stronk7@moodle.org>
Date: Sun, 20 Nov 2022 11:33:37 +0100
Subject: [PATCH] MDL-76389 output: Ensure we don't try to iterate over null

Just convert nulls to empty array before trying to iterate it.
---
 lib/outputlib.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/outputlib.php b/lib/outputlib.php
index f44c12e9c18..4e3fdbe5048 100644
--- a/lib/outputlib.php
+++ b/lib/outputlib.php
@@ -963,7 +963,7 @@ class theme_config {
                 $files['plugin_'.$plugin] = $sheetfile;
             }
 
-            $subplugintypes = core_component::get_subplugins("editor_{$plugin}");
+            $subplugintypes = core_component::get_subplugins("editor_{$plugin}") ?? [];
             // Fetch sheets for any editor subplugins.
             foreach ($subplugintypes as $plugintype => $subplugins) {
                 foreach ($subplugins as $subplugin) {