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Is this done? All the items are checked

I recently wrote a Chrome [polyfill for `browser.contentScripts.register`](https://github.com/bfred-it/content-scripts-register-polyfill#readme), if that was blocking you from using this API.

Additionally, I don't know if it's related but it I have this issue in tests that have to deal with multiple hosts: ```js const appApiMock = nock("http://localhost"); const externalHost =...