From 9e4038f06835a18b275291f1159cb29eb4473277 Mon Sep 17 00:00:00 2001
From: SaneSanders <129727118+SaneSanders@users.noreply.github.com>
Date: Thu, 24 Sep 2026 22:31:46 +0300
Subject: [PATCH] fix(canvas): stop the layer-order render loop during region
 drag

---
 src/renderer/src/features/workspace/canvasStacking.ts | 4 ++--
 tests/canvas-stacking.test.mjs                        | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/renderer/src/features/workspace/canvasStacking.ts b/src/renderer/src/features/workspace/canvasStacking.ts
index bf9415c6..4a8ee179 100644
--- a/src/renderer/src/features/workspace/canvasStacking.ts
+++ b/src/renderer/src/features/workspace/canvasStacking.ts
@@ -1,7 +1,7 @@
 import type { CameraState, SessionBounds } from "../../../../shared/contracts";
 
 export function reconcileCanvasLayerOrder(
-  current: readonly string[],
+  current: string[],
   active: readonly string[]
 ): string[] {
   const activeSet = new Set(active);
@@ -9,7 +9,7 @@ export function reconcileCanvasLayerOrder(
   for (const id of active) {
     if (!next.includes(id)) next.push(id);
   }
-  return next;
+  return next.length === current.length && next.every((id, index) => id === current[index]) ? current : next;
 }
 
 export function bringCanvasLayerToFront(current: readonly string[], id: string): string[] {
diff --git a/tests/canvas-stacking.test.mjs b/tests/canvas-stacking.test.mjs
index 804ded57..2329bc0a 100644
--- a/tests/canvas-stacking.test.mjs
+++ b/tests/canvas-stacking.test.mjs
@@ -32,6 +32,12 @@ test("layer reconciliation keeps user order and appends only new live windows",
   );
 });
 
+test("an unchanged layer order reconciles to the same array", () => {
+  const order = ["browser", "terminal:a", "note:n"];
+  assert.equal(reconcileCanvasLayerOrder(order, ["note:n", "terminal:a", "browser"]), order);
+  assert.notEqual(reconcileCanvasLayerOrder(order, ["terminal:a", "browser"]), order);
+});
+
 test("the native Browser surface is hidden only under a higher overlapping layer", () => {
   const map = new Map([
     ["browser", bounds(0, 0)],