From 562623d536e9e2c3473d13a5cccce8d14ce98870 Mon Sep 17 00:00:00 2001
From: Brittany Harris <6003769+brittharr@users.noreply.github.com>
Date: Tue, 23 Sep 2025 13:55:46 +0100
Subject: [PATCH] fix: use SSR format compatible with nginx SSI for props.id
 (#16820)

* fix: use SSR format compatible with nginx SSI for props.id

* changeset

---------

Co-authored-by: Rich Harris <hello@rich-harris.dev>
---
 .changeset/silly-schools-divide.md                  | 5 +++++
 packages/svelte/src/internal/client/dom/template.js | 2 +-
 packages/svelte/src/internal/server/index.js        | 2 +-
 3 files changed, 7 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/silly-schools-divide.md

diff --git a/.changeset/silly-schools-divide.md b/.changeset/silly-schools-divide.md
new file mode 100644
index 0000000000..ff36717063
--- /dev/null
+++ b/.changeset/silly-schools-divide.md
@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+fix: use nginx SSI-compatible comments for `$props.id()`
diff --git a/packages/svelte/src/internal/client/dom/template.js b/packages/svelte/src/internal/client/dom/template.js
index 135ca86610..c2443fda7a 100644
--- a/packages/svelte/src/internal/client/dom/template.js
+++ b/packages/svelte/src/internal/client/dom/template.js
@@ -365,7 +365,7 @@ export function props_id() {
 		hydrating &&
 		hydrate_node &&
 		hydrate_node.nodeType === COMMENT_NODE &&
-		hydrate_node.textContent?.startsWith(`#`)
+		hydrate_node.textContent?.startsWith(`$`)
 	) {
 		const id = hydrate_node.textContent.substring(1);
 		hydrate_next();
diff --git a/packages/svelte/src/internal/server/index.js b/packages/svelte/src/internal/server/index.js
index 3ff44f8030..50bb629c4d 100644
--- a/packages/svelte/src/internal/server/index.js
+++ b/packages/svelte/src/internal/server/index.js
@@ -448,7 +448,7 @@ export function once(get_value) {
  */
 export function props_id(renderer) {
 	const uid = renderer.global.uid();
-	renderer.push('<!--#' + uid + '-->');
+	renderer.push('<!--$' + uid + '-->');
 	return uid;
 }