4.9.1 cannot amend non-head draft revision from GUI
Created originally on Bitbucket by aayjaychan (Aay Jay Chan)
In previous versions, including 4.8.2 and 4.9, when evolve extension is enabled, "Amend current revision" is enabled when the parent of current directory is a non-head draft revision. But with 4.9.1, the button is greyed out.