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• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Problem Description

Previously described in #41432 (comment)

#41432 added an API to set a custom callback on popup window creation. This is necessary to, for example, have popups open in a BrowserView, rather than a new window.

With a BrowserView, this looks like:

mainWindow.webContents.setWindowOpenHandler((details) => {
  return {
    action: 'allow',
    createWindow: (options) => {
      const browserView = new BrowserView(options)
      mainWindow.addBrowserView(browserView)
      browserView.setBounds({ x: 0, y: 0, width: 640, height: 480 })
      return browserView.webContents
    }
  }
})

options contains a WebContents, which is passed through to the BrowserView constructor.

The problem is that WebContentsView does not support passing in a WebContents during it's construction, which makes this API impossible to use.

For now, I'm continuing to use a BrowserView in my app, but as BrowserView is deprecated, I'm concerned that once it's removed, I won't have any migration path to a newer version.

Proposed Solution

• Option 1: Allow passing in a WebContents to the WebContentsView constructor. This is already supported internally, and used by the BrowserView compatibility layer, it just isn't publicly exposed: https://github.com/electron/electron/blob/main/lib/browser/api/browser-view.ts#L13-L17. I'm not sure what the reason for hiding it was.
• Option 2: Change the setWindowOpenHandler API to work around this somehow. I expect that would be harder; I'm not sure exactly what the correct API would look like in that case.

Alternatives Considered

None.

Additional Information

No response