I'm using Word for Mac 2016 version 16.15.
Apparently the 'Shrink One Page'
command should be in found in Word Preferences > Ribbon & Toolbar
, but there's no sign of it there. See below screenshot.
Where is the 'Shrink One Page'
command?
On my system it is listed under All Commands, so try looking there.
I am running an Insider Fast release 16.16, so if you don't find it on your version with 16.15, then it is coming soon.