During merging, TortoiseGit offers a handy GUI to compare changes of both versions with the base file.
After resolving all conflicts and committing them, you can see the changes of a merge commit relative to both parents. Is there also a way to re-show the 3 way merge window for a merge commit from somebody else? Just seeing the individual changes makes it hard to judge, if the merge was performed correctly.
What I see now is two lists where I can check the changes with each parent, what I want is a list that only contains files changed in both branches and where I can see, how these changes where merged together.
I am aware, that I can manually check out the three files, open the three hand merge tool and load them (and delete the files afterwards). However this is rather tedious and not what you want to do, if you just want to quickly check a merge commit.