Mac bug or trick

Sometimes, Mac bugs just drive me crazy. The solution tricks are listed below for memo.

Always 1 unread notification in the mailbox.

solutions: http://www.mac52ipod.cn/post/apple-mac-os-x-mail-app-falsely-reports-unread-messages_3617.php

add a URL to dock

only work via safari :https://support.apple.com/en-us/HT201719

change default app

right click file and get Info: http://www.imore.com/how-change-default-apps-os-x

delete all ipad photoes from Mac

spotlight-> image capture

​