feat: pause on debugger for full page reloads in dev (#9305)

closes #9284

Author: Rich-Harris

.changeset/good-countries-enjoy.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': minor
+---
+
+feat: pause on debugger when falling back to full page reload during development

packages/kit/src/runtime/client/client.js

@@ -1181,6 +1181,15 @@ export function create_client(app, target) {
 				route
 			});
 		}
+
+		if (__SVELTEKIT_DEV__) {
+			console.error(
+				'An error occurred while loading the page. This will cause a full page reload. (This message will only appear during development.)'
+			);
+
+			debugger;
+		}
+
 		return await native_navigation(url);
 	}