>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3554239. --> Reported by: [jessebaker](https://www.drupal.org/user/3546546) Related to !270 !257 >>> <h3 id="overview">Overview</h3> <p>Originally reported in <span class="drupalorg-gitlab-issue-link project-issue-status-info project-issue-status-7"><a href="https://www.drupal.org/project/canvas_extjs/issues/3552862" title="Status: Closed (fixed)">#3552862: Annotations for child components within slots are lost</a></span></p> <p>When the overlay is built (by finding the HTML comments in the iFrame document whenever it changes) a walker goes through and finds the comments and then finds an HTML tag inside to build up a map of component ID (derived from the comment) to DOM elements in the iFrame.</p> <p>This issue occurs when that initial attempt to build the map fails to find an HTML element in the DOM inside the comments. This can happen if the initial payload does not contain the HTML and then components are asynchronously loaded in afterwards.</p> <h3 id="proposed-resolution">Proposed resolution</h3> <p>Ensure that if the DOM is mutated after load, we re-run the creation of the component to DOM element map.</p> <h3 id="ui-changes">User interface changes</h3> > Related issue: [Issue #3559579](https://www.drupal.org/node/3559579)