From 080b1d9a7cbe4c1ad592003748cea19607970769 Mon Sep 17 00:00:00 2001
From: Pierre Tachoire <pierre@lightpanda.io>
Date: Wed, 8 Oct 2025 13:55:17 +0200
Subject: [PATCH] drain micro task queue before reset ExecutionWorld and page

---
 src/browser/js/ExecutionWorld.zig | 6 ++++++
 src/browser/page.zig              | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/src/browser/js/ExecutionWorld.zig b/src/browser/js/ExecutionWorld.zig
index 04522a04..73603227 100644
--- a/src/browser/js/ExecutionWorld.zig
+++ b/src/browser/js/ExecutionWorld.zig
@@ -231,6 +231,12 @@ pub fn createContext(self: *ExecutionWorld, page: *Page, enter: bool, global_cal
 }
 
 pub fn removeContext(self: *ExecutionWorld) void {
+    // Force running the micro task to drain the queue before reseting the
+    // context arena.
+    // Tasks in the queue are relying to the arena memory could be present in
+    // the queue. Running them later could lead to invalid memory accesses.
+    self.env.runMicrotasks();
+
     self.context.?.deinit();
     self.context = null;
     _ = self.context_arena.reset(.{ .retain_with_limit = CONTEXT_ARENA_RETAIN });
diff --git a/src/browser/page.zig b/src/browser/page.zig
index ca36cd09..6cdc4f96 100644
--- a/src/browser/page.zig
+++ b/src/browser/page.zig
@@ -161,6 +161,9 @@ pub const Page = struct {
     }
 
     fn reset(self: *Page) void {
+        // Force running the micro task to drain the queue.
+        self.session.browser.env.runMicrotasks();
+
         self.scheduler.reset();
         self.http_client.abort();
         self.script_manager.reset();