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As the Git docs state, "core.ignoreCase" is not expected to be changed by the user [1]: Git relies on the proper configuration of this variable for your operating and file system. Modifying this value may result in unexpected behavior.

[1] https://git-scm.com/docs/git-config#Documentation/git-config.txt-coreignoreCase

Sorry, Chris, I should have read more carefully.

Seems to be a duplicate of https://smartgit.userecho.com/communities/1/topics/124-?

If so, please vote and comment there, then I will close this topic as duplicate.

This topic is about files from commits, not local (or Index) files.

Good point. Fixed for version 19.2 preview (SG-13044).

A screenshot of what is currently present (work-in-progress): for the selected lines (orange), you will see the restricted Navigation graph. In this graph, you will see:
  • all of the selected commits (orange dot)
  • all commits for predecessor lines, .i.e replaced lines (black dot)
  • auxiliary merge commits which are necessary to display the filtered lines with a reasonable structure (gray font)

This is actually something I'm currently working on for DeepGit. But maybe DeepGit will already be helpful to you in its current form: Query|Investigate .