QtCreator's (mercurial) hg diff does not provide side-by-side view

QtCreator's hg diff view does not provide side-by-side diff

Tools -> Mercurial -> Diff 

(Note: Tools -> Diff works properly to diff current unsaved file with side-by-side view)

Tested in both Qt Creator 4.6.2 and 4.7.0, still not fix, searched this issue to be claimed solved in 4.3.0 but it's not in 4.6.2 and afterwards.

Also test same tool environment to git diff which works properly.