Don't leave temp footprints attached to a board.

pcbnew/footprint.cpp

@@ -795,6 +795,8 @@ BOX2I FOOTPRINT::GetFpPadsLocalBbox() const
     for( PAD* pad : dummy.Pads() )
         bbox.Merge( pad->GetBoundingBox() );
 
+    dummy.SetParent( nullptr );
+
     return bbox;
 }
 

pcbnew/kicad_clipboard.cpp

@@ -94,6 +94,8 @@ void CLIPBOARD_IO::SaveSelection( const PCB_SELECTION& aSelected, bool isFootpri
         newFootprint.Move( VECTOR2I( -refPoint.x, -refPoint.y ) );
 
         Format( static_cast<BOARD_ITEM*>( &newFootprint ) );
+
+        newFootprint.SetParent( nullptr );
     }
     else if( isFootprintEditor )
     {
@@ -171,6 +173,8 @@ void CLIPBOARD_IO::SaveSelection( const PCB_SELECTION& aSelected, bool isFootpri
         partialFootprint.MoveAnchorPosition( moveVector );
 
         Format( &partialFootprint, 0 );
+
+        partialFootprint.SetParent( nullptr );
     }
     else
     {

pcbnew/tools/footprint_editor_control.cpp

@@ -44,6 +44,8 @@
 #include <kiway.h>
 #include <drc/drc_item.h>
 
+#include <memory>
+
 
 FOOTPRINT_EDITOR_CONTROL::FOOTPRINT_EDITOR_CONTROL() :
     PCB_TOOL_BASE( "pcbnew.ModuleEditor" ),
@@ -326,9 +328,14 @@ int FOOTPRINT_EDITOR_CONTROL::CutCopyFootprint( const TOOL_EVENT& aEvent )
     LIB_ID fpID = m_frame->GetTreeFPID();
 
     if( fpID == m_frame->GetLoadedFPID() )
-        m_copiedFootprint.reset( new FOOTPRINT( *m_frame->GetBoard()->GetFirstFootprint() ) );
+    {
+        m_copiedFootprint = std::make_unique<FOOTPRINT>( *m_frame->GetBoard()->GetFirstFootprint() );
+        m_copiedFootprint->SetParent( nullptr );
+    }
     else
+    {
         m_copiedFootprint.reset( m_frame->LoadFootprint( fpID ) );
+    }
 
     if( aEvent.IsAction( &PCB_ACTIONS::cutFootprint ) )
         DeleteFootprint( aEvent );