What's the keyboard shortcut to update posts? I've read that it's Alt + Shift + p, but that doesn't work on my Mac, nor does Ctrl + Shift + p.
I guess you need the Apple/Cmd key instead of the Alt key as the Ctrl/Strg is not the replacement for the Alt key.
So it should be ⌘ + Shift + P.
Note: I'm no Mac user, so you'll to search the proper replacement in case yourself.