How to avoid duplicate GIT submodule content after moving to another folder? warning: unable to rmdir 'xxx': Directory not empty

Question

Initial Situation / Goal

I have a GIT repository with a submodule let's say under <root>/Modules/SomePath/Example.

I want to move this submodule to a new location, let's say <root>/LocalStuff/NewName.

What I did

I basically followed How do I move an existing Git submodule within a Git repository and

• created folder <root>/LocalStuff/NewName

• used git mv /Modules/SomePath/Example/* /LocalStuff/NewName/

• in .gitmodules changed from

  [submodule "Modules/SomePath/Example"]
      path = Modules/SomePath/Example
      url = xxxxxxxxx
  

  to

  [submodule "LocalStuff/NewName"]
      path = LocalStuff/NewName
      url = xxxxxxxxx
  

• in the now LocalStuff/NewName/.git changed from

  gitdir: ../../.git/modules/Modules/SomePath/Example
  

  to

  gitdir: ../../.git/modules/LocalStuff/NewName
  

• created according folder <root>/.git/modules/LocalStuff/NewName

• moved all content from <root>/.git/modules/Modules/SomePath/Example into <root>/.git/modules/LocalStuff/NewName

• in the now <root>/.get/modules/LocalStuff/NewName/config

changed from

worktree = ../../../../Modules/SomePath/Example

to

worktree = ../../../../LocalStuff/NewName

Issue / Question

At first glance this worked fine and when I clone my branch everything is fine.

However, when switching between the "main" branch and my "MoveSubmodule" branch forth and back I get a warning

warning: unable to rmdir 'LocalStuff/NewName': Directory not empty

or accordingly

warning: unable to rmdir 'Modules/SomePath/Example': Directory not empty

with the result that the submodule is only there once but its content is there twice in the two locations. They are not tracked in GIT as changes though so even if I again delete them manually this is not a change I can commit.

Have I missed / screwed up anything?