message: Add constraint at top to prevent over render the message (mac)
diff: @@ -117,6 +117,7 @@ extern void *ctx;
  [self.messageView addConstraint:height];
  [self.contentView addConstraint:[NSLayoutConstraint constraintWithItem:self.contentView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self.messageView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:0]];
  [self.contentView addConstraint:[NSLayoutConstraint constraintWithItem:self.contentView attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:self.messageView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:0]];
  + [self.contentView addConstraint:[NSLayoutConstraint constraintWithItem:self.messageView attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationGreaterThanOrEqual toItem:self.contentView attribute:NSLayoutAttributeTop multiplier:1 constant:16]];
  // Hidden by default
  self.messageView.hidden = YES;
  