fix: set navigation.from to null on start without SSR

.changeset/quiet-owls-enter.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix: set `navigation.from` to `null` in `afterNavigate` on start when SSR is disabled

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

@@ -3755,12 +3755,16 @@ function create_navigation(
 
 	/** @type {(Navigation | AfterNavigate) & { type: T }} */
 	const navigation = /** @type {any} */ ({
-		from: {
-			params: current.params,
-			route: { id: current.route?.id ?? null },
-			url: current.url,
-			scroll: scroll_state()
-		},
+		// the app's first navigation has no page to come from
+		from:
+			type === 'enter'
+				? null
+				: {
+						params: current.params,
+						route: { id: current.route?.id ?? null },
+						url: current.url,
+						scroll: scroll_state()
+					},
 		to: url && {
 			params: target ? target.params : (intent?.params ?? null),
 			route: { id: target ? (target.route?.id ?? null) : (intent?.route?.id ?? null) },

packages/kit/test/apps/basics/src/routes/no-ssr/after-navigate/+page.svelte

@@ -3,11 +3,15 @@
 
 	let count = 0;
 	let type = '';
+	/** @type {string | undefined} */
+	let from;
 
 	afterNavigate((event) => {
 		count += 1;
 		type = event.type;
+		from = JSON.stringify(event.from);
 	});
 </script>
 
 <p>{type.toString()} {count}</p>
+<h2>from: {from}</h2>

packages/kit/test/apps/basics/test/playwright/client.test.js

@@ -507,6 +507,11 @@
 		await page.goto('/no-ssr/after-navigate');
 		await expect(page.locator('p')).toHaveText('enter 1');
 	});
+
+	test('afterNavigate has no origin on start', async ({ page }) => {
+		await page.goto('/no-ssr/after-navigate');
+		await expect(page.locator('h2')).toHaveText('from: null');
+	});
 });
 
 test.describe('$app/state', () => {
@@ -1530,7 +1535,7 @@
 		await expect(page.locator('[data-testid="stale-input"]')).toHaveValue('');
 	});
 
 	test('captures and restores function snapshots on shallow navigations', async ({ page }) => {
 		await page.goto('/snapshot/helper');
 		const input = page.locator('[data-testid="default"]');