diff --git a/plone/app/contentmenu/menu.py b/plone/app/contentmenu/menu.py
index e752899..7131c55 100644
--- a/plone/app/contentmenu/menu.py
+++ b/plone/app/contentmenu/menu.py
@@ -893,6 +893,9 @@ def getMenuItems(self, context, request):
                         "id": "workflow-transition-advanced",
                         "separator": "actionSeparator",
                         "class": "pat-plone-modal",
+                        "modal": json.dumps({
+                            "modalSizeClass": "modal-xl",
+                        }),
                     },
                     "submenu": None,
                 }