diff --git a/dzgui/views/components/buttonbox.py b/dzgui/views/components/buttonbox.py
index deac64c..ea79c45 100644
--- a/dzgui/views/components/buttonbox.py
+++ b/dzgui/views/components/buttonbox.py
@@ -19,7 +19,11 @@ if TYPE_CHECKING:
 
 class ContextualButton(Gtk.Button):
     def __init__(
-        self, label: str, opens: "NotebookPage" | None, tooltip: str, context: ButtonType
+        self,
+        label: str,
+        opens: "NotebookPage | None",
+        tooltip: str,
+        context: ButtonType,
     ) -> None:
         super().__init__(
             label=label,