Issue #3266717: Add out of the box support for the core Olivero theme

src/Annotation/CompatibilityShim.php

+<?php
+
+namespace Drupal\inline_all_css\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines a Compatibility Shim annotation.
+ *
+ * @Annotation
+ */
+class CompatibilityShim extends Plugin {
+
+  /**
+   * The plugin ID.
+   *
+   * @var string
+   */
+  public $id;
+
+  /**
+   * The assets that this shim applies to.
+   *
+   * @var string[]
+   */
+  public $assets = [];
+
+}