Exporting

Every object in a Project can be saved to a separate file.
Saving an object to an separate file is known as exporting. To export an object (File > Export) or (Ctrl + E).
You will get a dialog box asking for the filename.
A copy of the file is then moved. The original file is not moved.

Userforms

When you export a Userform any code associated with that userform will also get exported.
.frm - when exported
.frx File

link - excelvbasolutions.com/2021/01/frx-file.html 

If you try to delete a file from the Export File dialog box this seems to take forever.

'add a reference to "Microsoft Visual Basic for Applications Extensibility 5.3
Private Sub Document_Open() 

Dim sFolderPrefix As String 
Dim sFolderPath As String 

   sFolderPrefix = "C:\Temp\" 
   sFolderPath = "Folder\Source Code\Exported Code\" 
   
   Call ExportAllModules(sFolderPrefix & sFolderPath, "_2", True) 

End Sub 

Public Sub ExportAllModules( _ 
         ByVal sFolderPath As String, _ 
         ByVal sFileSuffix As String, _ 
         ByVal bSaveInSubFolders As Boolean) 
   
Dim VBProj As VBIDE.VBProject 
Dim VBComp As VBIDE.VBComponent 
Dim CodeMod As VBIDE.CodeModule 
        
   Set VBProj = ActiveDocument.VBProject 
        
   For Each VBComp In VBProj.VBComponents 
      If ((VBComp.Type = vbext_ct_Document) Or _ 
          (VBComp.Type = vbext_ct_StdModule) Or _ 
          (VBComp.Type = vbext_ct_MSForm)) Then 
          
         Set CodeMod = VBComp.CodeModule 
         
         Call ExportVBComponent(VBComp, sFolderPath, sFileSuffix, VBComp.CodeModule, True, bSaveInSubFolders) 
      End If 
   Next VBComp 
End Sub 

Public Function ExportVBComponent( _ 
         ByVal VBComp As VBIDE.VBComponent, _ 
         ByVal sFolderPath As String, _ 
         ByVal sFileSuffix As String, _ 
Optional ByVal sFileName As String, _ 
Optional ByVal bOverwriteExisting As Boolean = True, _ 
Optional ByVal bSaveInSubFolders As Boolean = False) As Boolean 

Dim sExtension As String 
Dim sFName As String 

    sExtension = GetFileExtension(VBComp:=VBComp) 

    sFName = sFileName 
    If InStr(1, sFName, ".", vbBinaryCompare) = 0 Then 
       If (sFileSuffix = "") Then 
          sFName = sFName & sExtension 
       Else 
          sFName = sFName & sFileSuffix & sExtension 
       End If 
    End If 

    If StrComp(Right(sFolderPath, 1), "\", vbBinaryCompare) <> 0 Then 
       sFolderPath = sFolderPath & "\" 
    End If 
         
    If (bSaveInSubFolders = False) Then 
        sFName = sFolderPath & sFName 
    End If 
    If (bSaveInSubFolders = True) Then 
        sFName = sFolderPath & VBComp.Name & "\" & sFName 
        If (Folder_Exists(sFolderPath & VBComp.Name) = False) Then 
           Call MkDir(sFolderPath & VBComp.Name) 
        End If 
    End If 
    
    If Dir(sFName, vbNormal + vbHidden + vbSystem) <> vbNullString Then 
        If (bOverwriteExisting = True) Then 
            Kill sFName 
        Else 
            ExportVBComponent = False 
            Exit Function 
        End If 
    End If 
    
    VBComp.Export FileName:=sFName 
    ExportVBComponent = True 
End Function 
    
Public Function GetFileExtension( _ 
         ByVal VBComp As VBIDE.VBComponent) As String 

    Select Case VBComp.Type 
        Case vbext_ct_ClassModule 
            GetFileExtension = ".cls" 
        Case vbext_ct_Document 
            GetFileExtension = ".cls" 
        Case vbext_ct_MSForm 
            GetFileExtension = ".frm" 
        Case vbext_ct_StdModule 
            GetFileExtension = ".bas" 
        Case Else 
            GetFileExtension = ".bas" 
    End Select 
End Function 

Public Function Folder_Exists( _ 
         ByVal sFolderPath As String) As Boolean 

Dim iTemp As Integer 
   On Error GoTo AnError 
   
   iTemp = GetAttr(sFolderPath) 
   Folder_Exists = True 
   
   Exit Function 
AnError: 
   Folder_Exists = False 
End Function 

Public Sub ExportVisualBasicCode() 
    Const Module = 1 
    Const ClassModule = 2 
    Const Form = 3 
    Const Document = 100 
    Const Padding = 24 
    
    Dim VBComponent As Object 
    Dim Count As Integer 
    Dim path As String 
    Dim directory As String 
    Dim extension As String 
    Dim fso As New FileSystemObject 

    directory = ActiveWorkbook.path '& "\Export-Folder"  
    Count = 0 

    If Not fso.FolderExists(directory) Then 
        Call fso.CreateFolder(directory) 
    End If 
    Set fso = Nothing 

    For Each VBComponent In ActiveWorkbook.VBProject.VBComponents 
        Select Case VBComponent.Type 
            Case ClassModule, Document 
                extension = ".cls" 
            Case Form 
                extension = ".frm" 
            Case Module 
                extension = ".bas" 
            Case Else 
                extension = ".txt" 
        End Select 

        path = directory & "\" & VBComponent.Name & extension 
        Call VBComponent.Export(path) 
        
        If Err.Number <> 0 Then 
            Call MsgBox("Failed to export " & VBComponent.Name & " to " & path, vbCritical) 
        Else 
            Count = Count + 1 
            Debug.Print "Exported " & Left(VBComponent.Name & ":" & Space(Padding), Padding) & path 
        End If 
    Next 
    
    Debug.Print "Successfully exported " & CStr(Count) & " VBA files to " & directory 
End Sub