After much searching, I have not found a satisfactory method that is easy to use to view the complete history of a moved file in Git and more importantly in Gitk. Using gi
Another alternative is to use the SourceTree application (GUI) developed by Atlassian. Inside the application you can right-click on the file and select "Log Selected ..."
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In the pop-up window it then allows you to "Follow renamed files":
I also use GitHub for Mac, but didn't see that kind of functionality in there, yet.
(I am not affiliated with either of them!)