Stamping does not work with node tool

Migrated from https://bugs.launchpad.net/inkscape/+bug/669162

Steps to reproduce:

• open Inkscape
• create a path
• click and hold a handle of the path
• press spacebar
• move the handle

What happened?

The path handle is moved.

What should have happened?

The path handle is moved and modified copies of the path are created ("stamping"). You can see how this worked in https://youtu.be/22b3c39saOQ?t=410.

Inkscape Version and Operating System:

• Inkscape Version: 1.1-dev (12e2a09, 2020-02-19)
• Operating System: Windows 10
• Operating System version: 10.0.18362

Migration info

• works in Inkscape 0.46 and 0.47;
• fails to work in the new node tool in Inkscape 0.48 (and 0.48+devel r9866), tested on OS X 10.5.8
• still not working in Arch Linux 64-bit, KDE Plasma 5, Inkscape 0.92pre1 15073 (GTK3)