Sorter Disappears in Clamshell Mode

Guys - I have sorter set to the left hand side of my secondary monitor. When I close my mac and go into clamshell mode, the sorter disappears. If I reopen the mac it reappears in the same spot on the secondary monitor that I set it at.

Note that when the shell closes, the screen flashes (as it should) and the sorter tab appears for a brief second and then disappears.
I am using DTP v2.11.1 on a 2017 15" MBP running High Sierra (10.13.6).

Please advise.

Development will have to look at this, as this is the first and only report we’ve had.