From 2bc97a06831022cbf098fdbefa7cb8851e79a4ea Mon Sep 17 00:00:00 2001
From: samfundev <samdinner@hotmail.com>
Date: Wed, 11 Feb 2026 15:52:37 -0500
Subject: [PATCH] fix: catch errors thrown during component mount to prevent
 source from losing tracking

---
 .changeset/wet-gifts-stare.md                 |  5 +++
 .../svelte/src/internal/client/dev/hmr.js     | 35 +++++++++++--------
 2 files changed, 25 insertions(+), 15 deletions(-)
 create mode 100644 .changeset/wet-gifts-stare.md

diff --git a/.changeset/wet-gifts-stare.md b/.changeset/wet-gifts-stare.md
new file mode 100644
index 0000000000..efb2a7baeb
--- /dev/null
+++ b/.changeset/wet-gifts-stare.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: catch errors thrown during component mount to prevent source from losing tracking
diff --git a/packages/svelte/src/internal/client/dev/hmr.js b/packages/svelte/src/internal/client/dev/hmr.js
index 9fa4e6ccbd..5650efb77f 100644
--- a/packages/svelte/src/internal/client/dev/hmr.js
+++ b/packages/svelte/src/internal/client/dev/hmr.js
@@ -38,21 +38,26 @@ export function hmr(fn) {
 				destroy_effect(effect);
 			}
 
-			effect = branch(() => {
-				// when the component is invalidated, replace it without transitions
-				if (ran) set_should_intro(false);
-
-				// preserve getters/setters
-				Object.defineProperties(
-					instance,
-					Object.getOwnPropertyDescriptors(
-						// @ts-expect-error
-						new.target ? new component(anchor, props) : component(anchor, props)
-					)
-				);
-
-				if (ran) set_should_intro(true);
-			});
+			try {
+				effect = branch(() => {
+					// when the component is invalidated, replace it without transitions
+					if (ran) set_should_intro(false);
+
+					// preserve getters/setters
+					Object.defineProperties(
+						instance,
+						Object.getOwnPropertyDescriptors(
+							// @ts-expect-error
+							new.target ? new component(anchor, props) : component(anchor, props)
+						)
+					);
+
+					if (ran) set_should_intro(true);
+				});
+			} catch (e) {
+				// eslint-disable-next-line no-console
+				console.error(e);
+			}
 		}, EFFECT_TRANSPARENT);
 
 		ran = true;