So far it is still only part of the Canari version of Edge, there are two more steps after this, the developer and beta versions before it gets into the public build. Of course I am not entirely sure how quickly this goes and if, for example, Canari features first are added to the other programs or if they can go straight from being in Canari to a public release. I have tried it and it's fantastic, you just press Control + Shift + O and like in the Windows Start Menu start typing a few letters of your Favourite and then arrow down to select from a list of choices.

Best regards,

Sieghard

I heard mention that Edge is experimenting with a new more accessible Favorites system that is available in the latest daily builds. I believe I saw mention of this about two weeks ago, therefore, it is probably making its way into the stable  insider builds soon.