How can I send&receive messages from a new created window?

[zgayjjf]

I'm using crx-bridge in a new project.

However, I can't receive a response when I use sendMessage in a window opened by the code below.

browser.windows.create({
  focused: true,
  url: `notification.html`,
  type: 'popup',
})

It is the same even if I called allowWindowMessaging in content-script and setNamespace in the created window.

Did I miss something?