rem: bool operator()( const GpgME::Key & key ) const { return key.keyListMode() & GpgME::Context::Validate ;
add: QString operator()( const GpgME::Key & key ) { return key.subkey(0).fingerprint();
context:     bool operator()( const GpgME::Key & key ) const {      return key.keyListMode() & GpgME::Context::Validate ;    }