From 4928a5e9490f7f547c6d5ecdc128eab97f926b52 Mon Sep 17 00:00:00 2001
From: Marin Atanasov <8436925+tyxla@users.noreply.github.com>
Date: Thu, 28 Nov 2024 11:02:55 +0200
Subject: [PATCH 1/2] Router: Fix addition and removal of empty classnames

---
 packages/router/src/router.tsx | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/packages/router/src/router.tsx b/packages/router/src/router.tsx
index ea0b218fa6a40..7c237ccce8da2 100644
--- a/packages/router/src/router.tsx
+++ b/packages/router/src/router.tsx
@@ -129,13 +129,17 @@ export function useHistory() {
 
 			await new Promise< void >( ( resolve ) => {
 				const classname = options.transition ?? '';
-				document.documentElement.classList.add( classname );
+				if ( classname ) {
+					document.documentElement.classList.add( classname );
+				}
 				// @ts-expect-error
 				const transition = document.startViewTransition( () =>
 					performPush()
 				);
 				transition.finished.finally( () => {
-					document.documentElement.classList.remove( classname );
+					if ( classname ) {
+						document.documentElement.classList.remove( classname );
+					}
 					resolve();
 				} );
 			} );

From bb9b71fccd29daea4af9b4e39509bbab2322d1fb Mon Sep 17 00:00:00 2001
From: Marin Atanasov <8436925+tyxla@users.noreply.github.com>
Date: Thu, 28 Nov 2024 12:11:48 +0200
Subject: [PATCH 2/2] Actually prevent transition

---
 packages/router/src/router.tsx | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/packages/router/src/router.tsx b/packages/router/src/router.tsx
index 7c237ccce8da2..34cc542c7b573 100644
--- a/packages/router/src/router.tsx
+++ b/packages/router/src/router.tsx
@@ -125,21 +125,18 @@ export function useHistory() {
 				! options.transition
 			) {
 				performPush();
+				return;
 			}
 
 			await new Promise< void >( ( resolve ) => {
 				const classname = options.transition ?? '';
-				if ( classname ) {
-					document.documentElement.classList.add( classname );
-				}
+				document.documentElement.classList.add( classname );
 				// @ts-expect-error
 				const transition = document.startViewTransition( () =>
 					performPush()
 				);
 				transition.finished.finally( () => {
-					if ( classname ) {
-						document.documentElement.classList.remove( classname );
-					}
+					document.documentElement.classList.remove( classname );
 					resolve();
 				} );
 			} );