Adam G-H
--- a/src/Activator/ActivationStatus.php
+++ b/src/Activator/ActivationStatus.php

 /**
 * Defines the possible states of a project in the current site.
+ *
+ * @api
+ *   This enum is covered by our backwards compatibility promise and can be
+ *   safely relied upon.
--- a/src/Element/ProjectBrowser.php
+++ b/src/Element/ProjectBrowser.php
 *    '#page_sizes' => [5, 10, 25],
 *  ];
 * @endcode
+ *
+ * @internal
+ *   This is an internal part of Project Browser and may be changed or removed
+ *   at any time. It should not be used by external code.
 */
 #[RenderElement('project_browser')]
-final class ProjectBrowser implements ElementInterface, ContainerFactoryPluginInterface {
+final class ProjectBrowser extends RenderElementBase implements ContainerFactoryPluginInterface {
--- a/src/ProjectType.php
+++ b/src/ProjectType.php
 * The different project types known to Project Browser.
 *
 * @see \Drupal\project_browser\ProjectBrowser\Project
+ *
+ * @api
+ *   This enum is covered by our backwards compatibility promise and can be
+ *   safely relied upon.
--- a/tests/src/FunctionalJavascript/ProjectBrowserUiTestTrait.php
+++ b/tests/src/FunctionalJavascript/ProjectBrowserUiTestTrait.php

 /**
 * Trait used by UI tests for testing actions like clicking and dragging.
+ *
+ * @internal
+ *   This is an internal part of Project Browser and may be changed or removed
+ *   at any time. It should not be used by external code.
--- a/project_browser.libraries.yml
+++ b/project_browser.libraries.yml
-svelte:
+app: