On a hunch, I unloaded Window Blinds and the controls immediately reappeared on an already open Dream Task configuration window. I reloaded WB, the controls remained, but when I closed DT and reopened it the controls were gone.
Windows 10 Enterprise (18362.19h1_release_svc_prod1.190628-1641)
WindowBlinds 10.83 (058 - Windows 10 Edition) - 64 bit OS
Window titlebar blur features are enabled on this operating system
Wblind.dll 2019/11/04 08:56:31
Wblind64.dll 2019/11/04 08:56:51
Wbsrv.dll 2019/05/03 23:29:46
WB10Config.exe 2019/06/25 14:37:54
Wbload.dll 2019/05/08 15:13:37
Screen10.exe 2017/03/28 08:53:17