This update is supposed to address wifi issues as well as some Mail issues. Personally the biggest gripe I’ve had with Apple / Mac OS X has existed since Mavericks and it has centered around Mail. I actually had to stop using Apple Mail in Mavericks as my GoDaddy IMAP account would not sync through Apple Mail. My messages arrive, sometimes late, and never reflect the read status after I read them on another device. I have to restart Mail for it to update. Some messages also seem not to appear until I restart, despite showing up fine on my laptop, iPhone or iPad. Very disapointing and so far Yosemite has not addressed this, and neither does this update. I guess I’ll stick with Airmail for now . . . 

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