diff --git a/addons/website/static/src/xml/website_form_editor.xml b/addons/website/static/src/xml/website_form_editor.xml
index 3cc82cafb5a..8d0e34bcdd9 100644
--- a/addons/website/static/src/xml/website_form_editor.xml
+++ b/addons/website/static/src/xml/website_form_editor.xml
@@ -332,7 +332,7 @@
                     class="s_website_form_input form-check-input"
                     t-att-id="recordId"
                     t-att-name="field.name"
-                    t-att-checked="record.selected and 'checked' or None"
+                    t-att="{checked: record.selected and 'checked' or None}"
                     t-att-value="record.id"
                     t-att-required="field.required || field.modelRequired || None"
                 />