Expanding group palette?

I see several years ago that expanding palettes are apparently available on @peternlewis' Mac.
Have they made it to everyone else's Mac yet?
Would be nice to have a palette lurking at the edge of a window.

The Palette themes include a checkbox for Shrink which is what this is, the palette shrinks to an icon until you hover over it.


I had forgotten (or didn't realize) that you can click on Palette Style to change the theme.