The scale image dialog allows you to select pixels per centimeter in the resolution setting, but the new image dialog is hard-coded to ppi. Fractional resolution also can't be set. Reproducible: Always Steps to Reproduce: 1. Launch Krita 2. Try to change resolution units
Thanks for the report!
WISHGROUP: Small Usability Fixes
It's being worked on here: https://invent.kde.org/graphics/krita/-/merge_requests/529
Git commit c4c56f3e7fdafbdb9313dec078813aeff22ee5ab by Dmitry Kazakov, on behalf of Sachin Jindal. Committed on 10/03/2021 at 13:17. Pushed by dkazakov into branch 'master'. Add comboBox in New Image dialog to allow resolution in ppc with ppi M +33 -40 libs/ui/forms/wdgnewimage.ui M +36 -6 libs/ui/widgets/kis_custom_image_widget.cc M +1 -0 libs/ui/widgets/kis_custom_image_widget.h https://invent.kde.org/graphics/krita/commit/c4c56f3e7fdafbdb9313dec078813aeff22ee5ab