Choosing 'Diff against current' for current branch doesn't clear previous range diff

Originally raised here: https://answers.atlassian.com/questions/100328/sourcetree-bug-in-diff

1. Right-click on any local branch that is not checked out and that is not the same as the current branch.
2. Choose DIFF against current. A list of files that are different will be displayed.
3. Right-clock on any local branch that is not checked out and that IS the same as the current branch.
4. Choose DIFF against current.

The file list from the previous diff will not be removed and will still show. Should show no files since there are no differences.