Patrick Rein uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-pre.759.mcz

==================== Summary ====================

Name: Collections-pre.759
Author: pre
Time: 30 June 2017, 11:39:43.025092 am
UUID: 730c33f1-c2a6-a246-9795-6d2c28af6005
Ancestors: Collections-eem.758

OrderedDictionary was missing the simple last selector.

=============== Diff against Collections-eem.758 ===============

Item was added:
+ ----- Method: OrderedDictionary>>last (in category 'accessing') -----
+ last
+ 	"Answer the last element of the receiver"
+ 
+ 	^ self atIndex: self size!