From dd305582b92ada6f1f5c1dde1edca8921b0c904f Mon Sep 17 00:00:00 2001
From: Dominic Gannaway <dg@domgan.com>
Date: Wed, 20 Nov 2024 12:43:16 +0000
Subject: [PATCH] side-effects agin

---
 packages/svelte/src/utils.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/packages/svelte/src/utils.js b/packages/svelte/src/utils.js
index 97ae0586a8..6f7d3e7517 100644
--- a/packages/svelte/src/utils.js
+++ b/packages/svelte/src/utils.js
@@ -216,15 +216,19 @@ const DOM_PROPERTIES = [
 	'srcObject'
 ];
 
-const DOM_PROPERTIES_MAP = new Map(
-	DOM_PROPERTIES.map((property) => [property.toLowerCase(), property])
-);
+/** @type {Map<string, string>} */
+let DOM_PROPERTIES_MAP;
 
 /**
  * @param {string} name
  * @returns {string | undefined}
  */
 export function get_dom_property(name) {
+	if (!DOM_PROPERTIES_MAP) {
+		DOM_PROPERTIES_MAP = new Map(
+			DOM_PROPERTIES.map((property) => [property.toLowerCase(), property])
+		);
+	}
 	return DOM_PROPERTIES_MAP.get(name);
 }