I updated to Firefox 99.0 yesterday, and ever since then, I cannot login to my icloud Mac Mail. I've spent hours on the phone with Apple customer support and they can't fix it. I can login to my Mac Mail via icloud.com when using a browser, but not on my computer itself. I think it's related to the 99.0 update (just based on the timing) but Apple isn't sure. My OS is High Sierra (10.13.6). Has anyone had a similar experience after updating? Any suggestions? Does Mozilla have a customer support number that I can call and talk to someone? I couldn't find a phone number under Contact Us. Thanks for the help!