[Sujeto]

>Is this manager advanced enough to replicate Vivaldi's tab tiling and stacking functionality?

No, but it can do a bunch of stuff, which you can try.

>also not sure why the screenshots devote 80% of space to non-addon functionality like page with some distracting chip images and colored tables

Was easier to take screenshots like this. But maybe I'll try cropping next time. I guess the idea was to show how it looks as a sidebar, or as a popup.