why cannot login into yahoo account throughfirefox

Can you show the issue? I can log into my account. see screenshot Did you try with Firefox in Troubleshoot Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_how-to-start-firefox-in-4troubleshoot-modesf5safe-modesf Did you try clearing the browser cache? https://support.mozilla.org/en-US/kb/how-clear-firefox-cache#