message: Fixes assert, triggert by selection release event outside the viewport.
diff: @@ -52,19 +52,24 @@ bool Selector::extend(Coordinate const& _coord)
  {
  assert(state_ != State::Complete && "In order extend a selection, the selector must be active (started).");
  + auto const coord = Coordinate{
  + clamp(_coord.row, 1u, viewport_.rows),
  + clamp(_coord.column, 1u, viewport_.columns)
  + };
  +
  state_ = State::InProgress;
  if (!isWordWiseSelection())
  - to_ = _coord;
  + to_ = coord;
  - else if (_coord > start_)
  + else if (coord > start_)
  {
  - to_ = _coord;
  + to_ = coord;
  extendSelectionForward();
  }
  else
  {
  - to_ = _coord;
  + to_ = coord;
  extendSelectionBackward();
  swapDirection();
  to_ = start_;
  