for( int i=folders.total; --i>=0; ) {
AssetPicon *picon = (AssetPicon*)folders.values[i];
if( !picon->in_use && !picon->persistent ) {
delete picon;
folders.remove_number(i);
for( int i=folders.total; --i>=0; ) {
AssetPicon *picon = (AssetPicon*)folders.values[i];
if( !picon->in_use && !picon->persistent ) {
delete picon;
folders.remove_number(i);