• https://mozilla.github.io/geckoview/
• sandbox compatible? Elaborate please
• PWAs would be awesome, agreed
• bad for casual, non-techie users, which expect pages to work
• every site that supports opensearch is supported, just go on a page supporting it, click on the address bar and click on the green plus symbol
• side bar exists as an API for extensions, same for containers! Mozilla provides an official extension: https://addons.mozilla.org/en-US/firefox/addon/side-view/

Watched one too many episodes of Not Just Bikes