This got removed upstream, but I found it really useful.
There might be a better way of doing this, but this works.
nnoremap <buffer> <nowait> <leader>r :Reword<cr>
nnoremap <buffer> <nowait> <leader>f :Fixup<cr>
nnoremap <buffer> <nowait> <leader>d :Drop<cr>
+
+" used to be part of vim, now removed see
+" https://github.com/tpope/vim-git/commit/3a96b1bca
+" https://github.com/tpope/vim-git/commit/6ee5e1f20
+let &l:keywordprg = 'git show'
+nnoremap <buffer> <expr> K col('.') < 7 && expand('<Lt>cword>') =~ '\X' && getline('.') =~ '^\w\+\s\+\x\+\>' ? 'wK' : 'K'
+
+let b:undo_ftplugin = "setl keywordprg< |exe 'nunmap <buffer> K'"