From [MS-RCPBCGR] 3.3.5.12.1:-
> ...The contents of this PDU SHOULD NOT be compressed.
>
> This PDU MUST NOT be sent to a client that has not indicated support for
> it by setting the RNS_UD_CS_SUPPORT_MONITOR_LAYOUT_PDU flag (0x0040)
> in the earlyCapabilityFlags field of the Client Core Data (section
> 2.2.1.3.2).
Also, 2.2.12.1 specifies the source channel must be zero.
In testing, a compressed monitor layout PDU causes mstsc.exe
to exit with a protocol error.
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