I am an experienced user of IT, have designed and managed my own websites, written simple programs, &c, and am online for hours every day. However, I am now over 80, and my sight is no longer good. When I try to compose a message in Mail on this MacBook Air, I can see the text in the body of the message, but all other text, for example what is shown in the sidebar, is illegible, or virtually so. This difficulty does not occur when I use my iPhone to compose messages, but of course Mail in iOS does not display any sidebar, and that is a feature that I need to use regularly. Can Apple do nothing to remedy this ?