diff --git a/CRM/Core/Payment/MJWTrait.php b/CRM/Core/Payment/MJWTrait.php
index a7975199acaef8af9d6c777bbe4c3e4ad690378f..4ae02d545e063ce9be8e1759075d1daea519002b 100644
--- a/CRM/Core/Payment/MJWTrait.php
+++ b/CRM/Core/Payment/MJWTrait.php
@@ -1,6 +1,12 @@
 <?php
-/**
- * https://civicrm.org/licensing
+/*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
  */
 
 use CRM_Mjwshared_ExtensionUtil as E;
diff --git a/CRM/Mjwshared/Resources.php b/CRM/Mjwshared/Resources.php
new file mode 100644
index 0000000000000000000000000000000000000000..01dfa14e0ecf29c97be98e21167cdfc77482e610
--- /dev/null
+++ b/CRM/Mjwshared/Resources.php
@@ -0,0 +1,100 @@
+<?php
+
+/**
+ * Class CRM_Mjwshared_Resources
+ *
+ * Currently (CiviCRM 5.24) \Civi::resources()->addVars() / CRM_Core_Resources::singleton()->addVars()
+ *   only allows adding to ajax-snippet or html-header region. But we need to add to billing-block region
+ * @todo See https://github.com/civicrm/civicrm-core/pull/16888 for a core fix which will allow us to
+ *    remove these compatibility functions
+ */
+class CRM_Mjwshared_Resources extends CRM_Core_Resources {
+
+  /**
+   * Added settings.
+   *
+   * Format is ($regionName => bool).
+   *
+   * @var array
+   */
+  protected $addedSettingsToRegion = [];
+
+  /**
+   * Add JavaScript variables to CRM.vars
+   *
+   * Example:
+   * From the server:
+   * CRM_Core_Resources::singleton()->addVars('myNamespace', array('foo' => 'bar'));
+   * Access var from javascript:
+   * CRM.vars.myNamespace.foo // "bar"
+   *
+   * @see http://wiki.civicrm.org/confluence/display/CRMDOC/Javascript+Reference
+   *
+   * @param string $nameSpace
+   *   Usually the name of your extension.
+   * @param array $vars
+   * @param string $region
+   *   The region to add settings to (eg. for payment processors usually billing-block
+   *
+   * @return CRM_Core_Resources
+   */
+  public static function compatAddVars($nameSpace, $vars, $region = NULL) {
+    $resourcesObject = CRM_Core_Resources::singleton();
+    $existing = CRM_Utils_Array::value($nameSpace, CRM_Utils_Array::value('vars', $resourcesObject->settings), []);
+    $vars = $resourcesObject->mergeSettings($existing, $vars);
+    self::compatAddSetting($resourcesObject, ['vars' => [$nameSpace => $vars]], $region);
+    return $resourcesObject;
+  }
+
+  /**
+   * Add JavaScript variables to the root of the CRM object.
+   * This function is usually reserved for low-level system use.
+   * Extensions and components should generally use addVars instead.
+   *
+   * @param \CRM_Core_Resources $resourcesObject
+   * @param array $settings
+   * @param string $region
+   *   The region to add settings to (eg. for payment processors usually billing-block
+   *
+   * @return CRM_Core_Resources
+   */
+  public static function compatAddSetting($resourcesObject, $settings, $region = NULL) {
+    if (!$region) {
+      $region = self::isAjaxMode() ? 'ajax-snippet' : 'html-header';
+    }
+    $resourcesObject->settings = $resourcesObject->mergeSettings($resourcesObject->settings, $settings);
+    if (isset($resourcesObject->addedSettingsToRegion[$region])) {
+      return $resourcesObject;
+    }
+    $resources = $resourcesObject;
+    $settingsResource = [
+      'callback' => function (&$snippet, &$html) use ($resources, $region) {
+        $html .= "\n" . self::compatRenderSetting($resources, $region);
+      },
+      'weight' => -100000,
+    ];
+    CRM_Core_Region::instance($region)->add($settingsResource);
+    $resourcesObject->addedSettingsToRegion[$region] = TRUE;
+    return $resourcesObject;
+  }
+
+  /**
+   * Helper fn for addSetting.
+   * Render JavaScript variables for the global CRM object.
+   *
+   * @param \CRM_Core_Resources $resourcesObject
+   *
+   * @return string
+   */
+  public static function compatRenderSetting($resourcesObject, $region) {
+    // On a standard page request we construct the CRM object from scratch
+    if ($region === 'html-header') {
+      $js = 'var CRM = ' . json_encode($resourcesObject->getSettings()) . ';';
+    }
+    // For an ajax request we append to it
+    else {
+      $js = 'CRM.$.extend(true, CRM, ' . json_encode($resourcesObject->getSettings()) . ');';
+    }
+    return sprintf("<script type=\"text/javascript\">\n%s\n</script>\n", $js);
+  }
+}