I published Emacs package vc-msg. It uses git-blame to show commit information of current line.

In the new version, it can display the correct commit information of current line.

For example, the line 6 at https://github.com/redguardtoo/test-git-blame/blob/master/hello.js is changed by three commits.

Select the partial of line 6 and run vc-msg-show , the correct commit is displayed.

Screenshots,