This problem only occurs when I preview my email in Earthlink web mail. I can get my email preview to reappear if I scroll or re-select the email. However, it may disappear again. Only the selected email preview disappears. The rest of the Earthlink web page remains. This only started in the last few weeks. I have been using Firefox as my default browser for years. The problem does not occur when I open and preview my emails in Earthlink web mail in the Google or Safari browser. I've tried having two browsers each with the same email previewed on screen at the same time to ensure it is not an earthlink web page problem. Only the preview on the Firefox browser disappears.