--- /dev/null
+{#
+/**
+ * @file
+ * Theme override for the IFrame entity browser. Template copied from core/modules/system/templates/page.html.twig
+ *
+ * @see template_preprocess_page()
+ * @see html.html.twig
+ */
+#}
+<div class="layout-container">
+
+ {#
+ We ommit most of the regions in this template, which generally includes
+ messages too. Since this is not desired we try to figure out where messages
+ live and display them separately.
+
+ @see entity_browser_preprocess_page__entity_browser__iframe()
+ #}
+ {{ messages }}
+
+ <main role="main">
+ <a id="main-content" tabindex="-1"></a>{# link is in html.html.twig #}
+
+ <div class="layout-content">
+
+ {{ page.content }}
+
+ </div>{# /.layout-content #}
+
+ </main>
+
+</div>{# /.layout-container #}