System.DebugLog not appearing in Console on 10.11?

My main develop Mac still runs 10.10, so I was not noticing this until now:

My app silently quits somehow early at start on a 10.11 system, with no message whatsoever. Console shows nothing, not even after I added System.DebugLog calls to App.Open and App.NewDocument.

But then I launched the app from the Terminal, by executing myapp.app/Contents/MacOS/myapp - and that did show the DebugLog msgs.

What’s up with them not showing up in Console under “All Messages”?

On 10.11 it works for me, however on 10.12 I get nothing.

NSLogMBS works?