From 2ca2979a46cf7410deb341c28fc063fadb48dbc1 Mon Sep 17 00:00:00 2001
From: Simon H <5968653+dummdidumm@users.noreply.github.com>
Date: Wed, 19 Jun 2024 20:17:22 +0200
Subject: [PATCH] fix: ensure element size bindings don't unsubscribe multiple
 times (#12091)

The `update` function could cause a read, which would end up being tracked in the effect, and said effect would then run multiple times when it should only run once

fixes #11934
fixes #12028
---
 .changeset/gorgeous-hats-wonder.md                           | 5 +++++
 .../svelte/src/internal/client/dom/elements/bindings/size.js | 4 +++-
 2 files changed, 8 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/gorgeous-hats-wonder.md

diff --git a/.changeset/gorgeous-hats-wonder.md b/.changeset/gorgeous-hats-wonder.md
new file mode 100644
index 0000000000..e1ce7bdaed
--- /dev/null
+++ b/.changeset/gorgeous-hats-wonder.md
@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+fix: ensure element size bindings don't unsubscribe multiple times from the resize observer
diff --git a/packages/svelte/src/internal/client/dom/elements/bindings/size.js b/packages/svelte/src/internal/client/dom/elements/bindings/size.js
index e0ad045d80..c817787497 100644
--- a/packages/svelte/src/internal/client/dom/elements/bindings/size.js
+++ b/packages/svelte/src/internal/client/dom/elements/bindings/size.js
@@ -1,4 +1,5 @@
 import { effect, teardown } from '../../../reactivity/effects.js';
+import { untrack } from '../../../runtime.js';
 
 /**
  * Resize observer singleton.
@@ -100,7 +101,8 @@ export function bind_element_size(element, type, update) {
 	var unsub = resize_observer_border_box.observe(element, () => update(element[type]));
 
 	effect(() => {
-		update(element[type]);
+		// The update could contain reads which should be ignored
+		untrack(() => update(element[type]));
 		return unsub;
 	});
 }