Amazon's Kindle Colorsoft users are reporting screen discoloration issues, including a yellow tint at the bottom of the display. The issue appears to be related to a recent software update, and some users have already received replacements or refunds from Amazon. While some users are unaffected by the issue, others find it distracting and annoying. Amazon has acknowledged the problem and is investigating.

Source: https://www.zdnet.com/article/kindle-colorsoft-users-reporting-screen-discoloration-issues-heres-amazons-response-for-now/