Inoperative links or buttons in the upper 1-2" on a web page may be caused by a faulty toolbar that invisibly overlaps the top of the web page. Other users have reported the Yahoo Toolbar and the Babylon extensions, among others, as causing the problem. Follow instructions in the articles below. Start in Firefox safe mode and experiment by turning extensions on/off to find the one. *See - *https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode (click the links for troubleshooting included in the article as well)