Move saving preferences out of the destructor.

For other reasons we wrap the adapters in a wxDataObject, which has
delayed destruction semantics, but that means the settings stuff may
no longer be around when the d'tor executes.

Fixes https://gitlab.com/kicad/code/kicad/issues/12371

common/widgets/lib_tree.cpp

@@ -182,9 +182,6 @@ LIB_TREE::~LIB_TREE()
 {
     // Stop the timer during destruction early to avoid potential race conditions (that do happen)
     m_debounceTimer->Stop();
-
-    // Save the column widths to the config file
-    m_adapter->SaveSettings();
 }
 
 

eeschema/picksymbol.cpp

@@ -199,6 +199,9 @@ PICKED_SYMBOL SCH_BASE_FRAME::PickSymbolFromLibTree( const SYMBOL_LIBRARY_FILTER
     if( dlg.ShowModal() == wxID_CANCEL )
         return PICKED_SYMBOL();
 
+    // Save any changes to column widths, etc.
+    modelAdapter->SaveSettings();
+
     PICKED_SYMBOL sel;
     LIB_ID id = dlg.GetSelectedLibId( &sel.Unit );
 

eeschema/symbol_editor/symbol_edit_frame.cpp

@@ -581,6 +581,9 @@ bool SYMBOL_EDIT_FRAME::canCloseWindow( wxCloseEvent& aEvent )
     if( !saveAllLibraries( true ) )
         return false;
 
+    // Save symbol tree column widths
+    m_libMgr->GetAdapter()->SaveSettings();
+
     return true;
 }
 

eeschema/symbol_viewer_frame.cpp

@@ -1016,6 +1016,9 @@ void SYMBOL_VIEWER_FRAME::OnSelectSymbol( wxCommandEvent& aEvent )
     if( dlg.ShowQuasiModal() == wxID_CANCEL )
         return;
 
+    // Save any changes to column widths, etc.
+    modelAdapter->SaveSettings();
+
     id = dlg.GetSelectedLibId( &unit );
 
     if( !id.IsValid() )

pcbnew/footprint_edit_frame.cpp

@@ -735,6 +735,9 @@ bool FOOTPRINT_EDIT_FRAME::canCloseWindow( wxCloseEvent& aEvent )
         }
     }
 
+    // Save footprint tree column widths
+    m_adapter->SaveSettings();
+
     return PCB_BASE_EDIT_FRAME::canCloseWindow( aEvent );
 }
 

pcbnew/load_select_footprint.cpp

@@ -271,6 +271,9 @@ FOOTPRINT* PCB_BASE_FRAME::SelectFootprintFromLibTree( LIB_ID aPreselect )
     if( dialog.ShowQuasiModal() == wxID_CANCEL )
         return nullptr;
 
+    // Save any changes to column widths, etc.
+    adapter->SaveSettings();
+
     if( dialog.IsExternalBrowserSelected() )
     {
         // SelectFootprintFromLibBrowser() returns the "full" footprint name, i.e.