If "All branches" or "Local branches" is selected, the buttons will be disabled.
Actions from the context menu continue to work as they implicitly set the target branch
through the identity of the clicked label patch.
Any other branch will re-enable the buttons.
Mind you, these buttons cannot operate on the clicked branch like the context menu.
Instead they always operate on the currently active branch (or its default remote).
That's why it's there, after all. This also makes the system
more robust and catches some more errors.
The next thing this enables is to also allow right-clicking
on refs in the commit list.
André Berg