Canvas borders are not supported in other color modes except rgb mode.
I usually work with cmyk, so I make the background white and it's so inconvenient to see the image in advance.
I checked the symptoms on several computers and someone said they don't have these symptoms.
Can you give me 5 seconds to test it for me? Is there a computer that develops similar symptoms?
I use the latest version of Windows 10 and Photoshop. I asked the customer center about this issue twice and Adobe confirmed it, but it was not reflected in the update.