No mention on updated native apps (mail, calendar, Safari, etc) ???
Yes there is:
Files attached to a blank email from 3rd-party applications may not be attached. Workaround: Save file then attach to message manually.
Safari
Safari Technology Preview does not yet work on macOS 10.12. Please test website and Safari Extension compatibility using Safari included with macOS 10.12.
The Web Content process may exit unexpectedly if shipping method is set to None and Shipping Address is required.
If your Safari App Extension crashes with a DYLD error message stating that the libswiftSafariServices.dylib could not be loaded, do a clean build of the containing app.