pixelize tool clipping option missing?

[SledgeS5]

This is the Pixelise tool shown in the documentation for 2.10 here: gimp 2.10 pixelise tool help

But I can't find this clipping option for this tool in gimp 2.10 for windows 10 x64 or 2.99 for win10 x64.

Am I missing something? Does the documentation show some features that don't exist yet? Is this only available on different platforms?

It looks really ugly having semi-pixels at the edges of the selection.