[leleat]

There is also

  git update-index --[no]-skip-worktree

for files that are already tracked. This can be useful for some local experimentation... it's just a bit annoying to use because it's not really surfaced anywhere by git (kinda). You need to remember that you set it; otherwise other operations like checkouts may be blocked.

[oezi]

This is what I use for making changes to local settings.json. Works nicely.