Reinitializing a repository using "git init --separate-git-dir" turns all overlay icons to added

TortoiseGit is showing "added" overlay icon after changes committed to the repository separated from working tree.

Repro steps:

C:\gitTest contains test1 and rep directories. test1 contains one commited file.

cd C:\gitTest\test1

C:\gitTest\test1>git init --separate-git-dir ../rep

Reinitialized existing Git repository in C:/gitTest3/rep/

After Git repository is separated committing changes does not change overlay icon and TortoiseGit showing "added' icon instead of "normal" one.

Why does not overlay icon change to "normal" green icon after committing changes? Is there work around to this problem with overlay icons? Note: overlay icon is changing to "normal" if test1 contains .git directory and repository is not separated from working tree. This problem happened with TortoiseGit-2.3.0.0-64bit, TortoiseGit-2.4.0.0-64bit and TortoiseGit-2.4.0.0-64bit

thanks