Add a way for extension main files to launch urls in a browser window

[Sebastian-ubs]

User Story
As a extension developer, I want to be able to open a website in the user's browser so that I can send them to more information.

Example use case: Open the currently loaded website of a website viewer tab in the web browser: Because website viewer is a url webview, there is no other place to add such action than in the menu.

Description
It's possible to launch a url in the web browser by clicking on a link in a web view, but there is not way to do that from the extension host process, e.g. add a menu entry that would open a url in the browser.

window.open is not available and importing packages (e.g. from electron) throws

Error: Requiring other than papi is not allowed in extensions!

Implementation idea

Testing ideas