I am a newbie using Krita 3.1.4 running under Windows 7 Pro (64-bit). When I create a new document (File >New), select Custom Document, change the Width and Height to inches, and enter 2 (width) by 1 (height), at 300 PPI, I get a thin, straight line on the screen. To get what I wanted, I had to resize the canvas (Image > Resize Canvas).
Happens in 4.0.0-pre-alpha (git 883b78a) as well. I suspect the values aren't interpreted right somehow.
Created attachment 107682 [details] seems to be working here Weird, I didn't get this with 3.2.1 on Windows, tried just now.
Yes, it worked for me as well.
For me this works with git master. Also if I am not mistaken the bug reported also posted on the forum and said that after updating it works for them now. https://forum.kde.org/viewtopic.php?f=139&t=141675&p=380779&hilit=krita+canvas+inches#p380779