This bug is very old. I don't remember a time when it worked.
RDCMan v2.90 Doesn't honor 'Desktop background'
Rhun
21
Reputation points
I am using RDCMan v2.90 and find that when connecting to Windows Server 2012, 2012R2, 2016 or 2019 the desktop background is shown even when RDCMan Experience settings have the Desktop background option disabled.
I have also tried setting connection speed to values that disable this setting as well with no change.
mstsc.exe works as expected to the same 2019 server tested above, i.e. desktop background image is not shown.
(v10.0.19041, RD Protocol v10.8)
I am assuming this is just a bug with RDCMan so thought I would post it here.