From 597883a1794f0f00e27fa70fc01d4ab31db7b9e8 Mon Sep 17 00:00:00 2001
From: Classic298 <27028174+Classic298@users.noreply.github.com>
Date: Sun, 1 Mar 2026 20:46:05 +0100
Subject: [PATCH] perf: use structuredClone and fast-path comparison in
 UserMessage (#22098)

Same optimization as the merged ResponseMessage PR: replace JSON.parse(JSON.stringify()) with structuredClone and add an O(1) fast-path check on content before falling back to full JSON.stringify comparison.
---
 src/lib/components/chat/Messages/UserMessage.svelte | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/lib/components/chat/Messages/UserMessage.svelte b/src/lib/components/chat/Messages/UserMessage.svelte
index 0c512e8f2..201c04de5 100644
--- a/src/lib/components/chat/Messages/UserMessage.svelte
+++ b/src/lib/components/chat/Messages/UserMessage.svelte
@@ -52,10 +52,15 @@
 	let messageEditTextAreaElement: HTMLTextAreaElement;
 	let editScrollContainer: HTMLDivElement;
 
-	let message = JSON.parse(JSON.stringify(history.messages[messageId]));
+	let message = structuredClone(history.messages[messageId]);
 	$: if (history.messages) {
-		if (JSON.stringify(message) !== JSON.stringify(history.messages[messageId])) {
-			message = JSON.parse(JSON.stringify(history.messages[messageId]));
+		const source = history.messages[messageId];
+		if (source) {
+			if (message.content !== source.content) {
+				message = structuredClone(source);
+			} else if (JSON.stringify(message) !== JSON.stringify(source)) {
+				message = structuredClone(source);
+			}
 		}
 	}