a

astro.config.mjs

@@ -13,6 +13,13 @@ export default defineConfig({
 	vite: {
 		server: {
 			allowedHosts: ["nin0-pc.buri-roach.ts.net"]
+		},
+		resolve: {
+			// Use react-dom/server.edge instead of react-dom/server.browser for React 19.
+			// Without this, MessageChannel from node:worker_threads needs to be polyfilled.
+			alias: import.meta.env.PROD && {
+				"react-dom/server": "react-dom/server.edge"
+			}
 		}
 	}
 });