Trace/Debug in ServerSide Trigger, blank window (17r5+)

client/server, 17r5, r6, ms windows
I’ve discovered (unless I’m wrong) that if a table trigger hits something that would bring up trace/debug window on Server , the window comes up blank.

The only thing I can do is hit the red X close box.

Is this a bug? or a feature removal?

FYI, I confirmed that this is a bug. Started in 17R4.

ACI0099903: [142330] TRACE in table trigger displays blank debugger window