How to see the difference between two packages by using Monticello?
Do you mean two versions of the same package, or two different packages?
Two versions of the same package
To compare versions A & B of a package...
1. In Monticello <Open> the repository
2. Select package version A
3. Click <History>
4. From the history, right-click on package version B
5. then click <view changes -> "package B">
If however package B is not in the history of package A, then I think you can
only load package A, then select package B and click <Changes>
hope that is clear enough,
Thank you, it worked!
Is it possible to document it somewhere?
Pharo By Example is probably a good place - if it isn't already.
Cross-posting for history purposes.