diff --git a/capellambse_context_diagrams/context.py b/capellambse_context_diagrams/context.py
index fc4751d5..41f85941 100644
--- a/capellambse_context_diagrams/context.py
+++ b/capellambse_context_diagrams/context.py
@@ -349,8 +349,9 @@ def _create_diagram(self, params: dict[str, t.Any]) -> cdiagram.Diagram:
             "display_symbols_as_boxes",
             "slim_center_box",
         ]:
-            if override := params.pop(param_name, None) is not None:
+            if (override := params.pop(param_name, None)) is not None:
                 setattr(self, param_name, override)
+
         data = params.get("elkdata") or get_elkdata(self, params)
         layout = try_to_layout(data)
         add_context(layout, params.get("is_legend", False))