Migrate to Ant Design v6: zeroRuntime & CSS Variables

Why Ant Design v6 matters Ant Design v6 is a technical, performance-first upgrade. It modernizes the styling engine around CSS variables, raises the minimum React version to 18, and introduces a zeroRuntime mode that can dramatically reduce runtime cost and bundle size. If you maintain a production UI built on Ant Design, planning an Ant Design v6 migration is a great opportunity to remove legacy workarounds and optimize theming and CSS delivery — but the change also has concrete gotchas that will bite if you rush it. Before you upgrade: hard preconditions Treat v6 as a checkpoint you must pass before flipping the switch: Upgrade to React 18 or newer. v6 drops support for React ≤17. Bump your icons package: upgrade @ant-design/icons to v6+. Note: @ant-design/icons@6 is not compatible with antd@5, so upgrade them together. Remove any v5 React-19 patches (e.g., @ant-design/v5-patch-for-react-19) — v6 assumes the newer React runtime semantics. Confirm your b