Some origins can contain different applications with different levels of security requirements. In those cases, it can be beneficial to prevent scripts running in one application from being able to open and script pages of another same-origin application. In such cases, it can be beneficial for a document to ensure its opener cannot script it, even if the opener document is a same-origin one. The `noopener-allow-popups` Cross-Origin-Opener-Policy value will allow documents to define that.
Compatibility risk: As this feature adds a new COOP value, it doesn't run a risk of colliding with existing values. Where we may see some risk is when developers start using this value in ways that would surprise other teams on their origins. (as they would no longer have scripting access to opened documents) I don't expect that to happen often, and if it would it's something that developers would find out at development time. So I don't expect that to impact users. Interoperability risk: Too early to tell as positions/PR was just filed.
Does this intent deprecate or change behavior of existing APIs, such that it has potentially high risk for Android WebView-based applications?
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