Found a preview function for Files app in the dock

[aranshaw]

http://imgur.com/a/SI06P

To do this briefly press and hold files while its in the dock

 

[Hyloba]

At first I thought that was macOS, which is good.

 

[FurbyUK]

http://imgur.com/a/SI06P

To do this briefly press and hold files while its in the dock

yea, that was in the keynote