Bug 199708 – history.back/forward does not trigger the popstate event synchronously

• Status: RESOLVED
• Resolution: WONTFIX
• Component: History

Steps to reproduce the problem:
1. open https://www.google.com
2. open webconsole
3. input 
```
  history.pushState("/", {}, "");
  let flag = false;
  window.addEventListener("popstate", () => {
    console.log({ flag });
  });
  flag = true;
  history.back();
  queueMicrotask(() => (flag = false));
```

What is the expected behavior?
output `{ flag: true }`

What went wrong?
output `{ flag: false }`

https://www.fxsitecompat.dev/en-CA/docs/2019/history-navigation-methods-are-now-asynchronous/

Firefox has modified the behavior