PowerPoint - Break link of picture inserted and linked

[Macro_learner]

Good morning,

I searched the web for an answer, tested few but without success. Please move this to the correct forum if needed.

I have a PowerPoint with several slides, each with one or more pictures linked to saved png files.
They were added using this path:
Insert Tab / Pictures / This Device / *select picture png* / Insert and link

Once the PowerPoint is ready I want to run a Macro to break the links of these pictures.
I tried the VBA below and some variations but it doesn't work.
I'm new to VBA so I assume the issue is that these "linked pictures" are not "msoPlaceholder", but I can't fine online what other "mso*" exists or what ".type" is a linked picture.

Sub BreakAllLinks()

Dim oSld As Slide
Dim oSh As Shape

For Each oSld In ActivePresentation.Slides
    For Each oSh In oSld.Shapes
        If oSh.Type = msoPlaceholder Then
               oSh.LinkFormat.BreakLink
        End If
    Next   ' Shape
Next   ' Slide

End Sub

Hope someone can help me.
Thanks.