2024-01-02: Site is back on track, self-hosted on a rpi because you get the Internet you fund.
2025-02-06: Oh well, some power grid issues caused the rpi to reboot, I really should configure uwsgi to restart automatically --'

d4d0aa16-9948-41a4-aa85-d97ff9646993
System.ItemParticipants_3.X

d4d0aa16-9948-41a4-aa85-d97ff9646993 System.ItemParticipants_3.X

PKEY_ItemParticipants

//  Name:     System.ItemParticipants -- PKEY_ItemParticipants
//  Type:     Multivalue String -- VT_VECTOR | VT_LPWSTR  (For variants: VT_ARRAY | VT_BSTR)
//  FormatID: D4D0AA16-9948-41A4-AA85-D97FF9646993, 100
//  
//  This is the generic list of people associated with an item and who contributed 
//  to the item. 
//  
//  For example, this is the combination of people in the To list, Cc list and 
//  sender of an email message.
0 Microsoft propkey.h
System.ItemParticipants_3.X

2.X PROPERTY : D5CDD505-2E9C-101B-9397-08002B2CF9AE/'People'
3.X PROPERTY : D4D0AA16-9948-41A4-AA85-D97FF9646993/100

from https://msdn.microsoft.com/fr-fr/library/windows/desktop/bb419046(v=vs.85).aspx
0 MS Property Mappings (from WDS 2.x to 3.x)
Include/10.0.16299.0/um/propkey.h:2269

//  FormatID: {D4D0AA16-9948-41A4-AA85-D97FF9646993}, 100
in Include/10.0.16299.0/um/propkey.h:2269
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