When I am using gitk GUI and I checkout to (create) remote-tracking branch (right-click and checkout) (origin/type/branch), branch named branch is created - not type/branch. Is there possibility how to preserve also the part before the last slash?
Unfortunately, at the moment there is no way to make gitk preserve anything before the last / when creating a local branch from a remote tracking branch.
You need to use the CLI, or you may want to consider some other graphical tools, i.e. SourceTree.