A new version of Monticello was added to project The Inbox:
http://source.squeak.org/inbox/Monticello-nice.734.mcz

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

Name: Monticello-nice.734
Author: nice
Time: 30 December 2020, 3:57:21.60758 pm
UUID: 863f642a-7795-4eb6-aa6b-76a5af3a8504
Ancestors: Monticello-mt.733

Workaround version history browser bug when 'working copy' is selected.

The snapshot is searched in repositoryGroup, and logically, none is found.
Note that the self selectedInfo isKindOf: MCWorkingCopyAncestry, which does not behave as a regular MCVersionInfo, it does not even answer to versionName...
This somehow accelerate the failure thru an ifError: [] handling, but at the end, the selectedSnapshot is still nil which makes the 'view changes from...' menu fail.

The workaround is not very nice, it use implicit knowledge that 'working copy' will be at top of list (index = 1).

If you can think of nicer fix, please raise voice.

=============== Diff against Monticello-mt.733 ===============

Item was changed:
  ----- Method: MCVersionHistoryBrowser>>selectedSnapshot (in category 'accessing') -----
  selectedSnapshot
+ 	index = 1 ifTrue: [^package snapshot].
  	^ self snapshotForInfo: self selectedInfo!