I lost the ability to log in to my yahoo email with firefox. This occurred after your recent firefox update. My network solutions email account and everything else still works. What's happening and how can I fix it?.

I’d first test whether it’s Yahoo specifically rather than the Firefox update itself. Try opening Yahoo Mail in a Private Window. If you can log in there, something in your normal Firefox profile'''—often an extension, cookies, or site permissions—'''is getting in the way. If that doesn’t help, clear cookies/site data for Yahoo only rather than wiping all your browsing '''data: click the padlock/shield next to the Yahoo address → Clear cookies and site data, then restart Firefox and try again.''' Also check that Enhanced Tracking Protection isn’t set to Strict for Yahoo. If you’re getting a specific error message during login, post that wording because it would narrow this down considerably.