If importing keymap with the same name as the built-in ones (like "Blender", "Industrial Compatible"), those entries will become stale and can't be removed from the UI because when removing preset it checks the name against builtin ones. This patch fixes the problem from the importing side and disallow names that are the same with builtin ones from being imported (They will be renamed upon importing). Pull Request: https://projects.blender.org/blender/blender/pulls/142697