XnView MP: decreasing canvas width on 1-bit b/w image creates strips on the right side

[pegas]

XnView: MP 1.5.5-1.8.3 - 64 bit
OS: Windows 11 - 64bit

Result of the "Canvas resize" command applied to black-and-white image, with the width decreased, from the position on the right, creates white/black vertical strips on the right side.

Effect: image change is different

To reproduce:
1. Open some file with black-and-white image.
2. Choose "Image/Canvas resize" command.
3. Decrease value of Width by 100.
4. Press OK.

Actual behaviour (bug): The right side of image is filled with white or black vertical stripes.
Expected behaviour: The right side of image should look as an original.

[user0]

can reproduce
need step 3.2 set Position to Top-Center, Center, Bottom-Center, Top-Right, Center-Right or Bottom-Right