Oh god. It has a pleasant color scheme, but this is an awful idea. By trying to recreate windows and bookmarks in the web app you're at best just implementing redundant features and getting in the way of the native browser features by trying to showcase yours, at worst breaking regular web usage entirely.
Take their right click menu for items to select whether you want an in-app tab or real browser tab. Congrats, you've broken UX by making the native browser right-click menu unavailable on link items, and because you've only implemented this on some things most of your content is not deep linkable as navigation is a cursed in-app feature.
This is as usual a fun tech demo, but it should not be used for anything in the real world.
Take their right click menu for items to select whether you want an in-app tab or real browser tab. Congrats, you've broken UX by making the native browser right-click menu unavailable on link items, and because you've only implemented this on some things most of your content is not deep linkable as navigation is a cursed in-app feature.
This is as usual a fun tech demo, but it should not be used for anything in the real world.