Works for me. see screenshot Have you tried 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 clear your browser cache? https://support.mozilla.org/en-US/kb/clear-cookies-and-site-data-firefox

When I use troubleshooting mode I get the attached image. Hopefully the image uploads. I have never had a problem getting into yahoo mail until recently after a firefox update. I just don't know what has changed.

I also cleared my cookies and site data. No help.

I loaded the latest experimental version for my linux ubuntu 149.0a1 Nightly 2-3-26. Still unable to log in to yahoo email.

Works for me in Nightly. see screenshot Try downloading Firefox from Mozilla, run firefox-bin from the folder and see if you have the same issue. https://www.mozilla.org/en-US/firefox/all/#product-desktop-release What Desktop? X11 or Wayland? Try using your os on a live usb stick and see if you have the same issue.

Operating System: openSUSE Tumbleweed 20260202 KDE Plasma Version: 6.5.5 KDE Frameworks Version: 6.22.0 Qt Version: 6.10.1 Kernel Version: 6.18.8-1-default (64-bit) Graphics Platform: X11 Processors: 16 × AMD Ryzen 7 5825U with Radeon Graphics Memory: 64 GiB of RAM (62.1 GiB usable) Graphics Processor: AMD Radeon Graphics Manufacturer: HP Product Name: HP ProBook 455 15.6 inch G9 Notebook PC