From f0fc968e78058534ded3ba47d3ec5e3e13372dc1 Mon Sep 17 00:00:00 2001
From: Alex Cui <cuizhihui030925@outlook.com>
Date: Thu, 27 Aug 2026 00:33:41 +0800
Subject: [PATCH 1/2] fix(vm): thread status check after executing hats

---
 packages/scratch-vm/src/engine/runtime.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/packages/scratch-vm/src/engine/runtime.js b/packages/scratch-vm/src/engine/runtime.js
index 85ee4ae9452..407d625c187 100644
--- a/packages/scratch-vm/src/engine/runtime.js
+++ b/packages/scratch-vm/src/engine/runtime.js
@@ -1926,6 +1926,10 @@ class Runtime extends EventEmitter {
         // threads are stepped. See ScratchRuntime.as for original implementation
         newThreads.forEach(thread => {
             execute(this.sequencer, thread);
+            if (thread.status === Thread.STATUS_DONE) {
+                // Thread might be done after `execute`.
+                return;
+            }
             thread.goToNextBlock();
         });
         return newThreads;

From 8fcddc1676741f2ac0e2e6696e4eb2dea5a8db01 Mon Sep 17 00:00:00 2001
From: Alex Cui <cuizhihui030925@outlook.com>
Date: Thu, 27 Aug 2026 00:34:47 +0800
Subject: [PATCH 2/2] fix(vm): typo of thread.stackFrames in retireThread

---
 packages/scratch-vm/src/engine/sequencer.js | 2 +-
 packages/scratch-vm/src/engine/thread.js    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/scratch-vm/src/engine/sequencer.js b/packages/scratch-vm/src/engine/sequencer.js
index d37a466de48..8972309bbf3 100644
--- a/packages/scratch-vm/src/engine/sequencer.js
+++ b/packages/scratch-vm/src/engine/sequencer.js
@@ -352,7 +352,7 @@ class Sequencer {
      */
     retireThread (thread) {
         thread.stack = [];
-        thread.stackFrame = [];
+        thread.stackFrames = [];
         thread.requestScriptGlowInFrame = false;
         thread.status = Thread.STATUS_DONE;
     }
diff --git a/packages/scratch-vm/src/engine/thread.js b/packages/scratch-vm/src/engine/thread.js
index 5cc3e6a8480..2aaf35943e2 100644
--- a/packages/scratch-vm/src/engine/thread.js
+++ b/packages/scratch-vm/src/engine/thread.js
@@ -251,7 +251,7 @@ class Thread {
     /**
      * Reset the stack frame for use by the next block.
      * (avoids popping and re-pushing a new stack frame - keeps the warpmode the same
-     * @param {string} blockId Block ID to push to stack.
+     * @param {string | null} blockId Block ID to push to stack.
      */
     reuseStackForNextBlock (blockId) {
         this.stack[this.stack.length - 1] = blockId;