We can display line breaks in message box with AX 2012. But it does not work with D365fO(AX7).

Code example: Box::warning(‘A’+’\n’+’B’);

Dynamics AX development team mentions that this is the limitation of D365FO due to security reason.

But the message without line break is very difficult to read because multiple messages are shown as 1 line.

The partner requests to support line break in message box.