>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3228149. --> Reported by: [mglaman](https://www.drupal.org/user/2416470) Related to !6 >>> <h3 id="summary-problem-motivation">Problem/Motivation</h3> <p>When using Layout Builder with Menu Block, the menu blocks are duplicated. This is due to system_menu_block and menu_block derivatives conflicting. It looks like Menu Block has an interesting workaround here for normal pages: <a href="https://git.drupalcode.org/project/menu_block/-/blob/8.x-1.x/src/EventSubscriber/MenuBlockKernelViewSubscriber.php">https://git.drupalcode.org/project/menu_block/-/blob/8.x-1.x/src/EventSubscriber/MenuBlockKernelViewSubscriber.php</a>. Something may need to be done for Layout builder.</p> <h4 id="summary-steps-reproduce">Steps to reproduce</h4> <p>Install Layout Builder + Menu Block. Add a block in a layout: see two main menu blocks</p> <h3 id="summary-proposed-resolution">Proposed resolution</h3> <p>Only show Menu Block derivatives</p> <h3 id="summary-remaining-tasks">Remaining tasks</h3> <h3 id="summary-ui-changes">User interface changes</h3> <h3 id="summary-api-changes">API changes</h3> <h3 id="summary-data-model-changes">Data model changes</h3>