Grayjay is a cutting-edge app that serves as a video player and source aggregator. It allows you to stream and organize videos from various sources, providing a unified platform for your entertainment needs.
It's mostly used as a YouTube frontend^. However, it is now launching as a desktop app for Linux, Mac and Windows.
Does it have tabs? if not I can't see myself caring.
It doesn't look like it does. It has multiple stackable windows, though.