In my machine, the culprit found by use of ShellExView was (strangely enough) from McAfee:
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Extension Name : McCtxFrmWrk Class
Disabled : Yes
Type : Context Menu
Description : McAfee ContextMenu Framework
Version : 15,0,179,0
Product Name : McAfee SecurityCenter
Company : McAfee, Inc.
My Computer : No
Desktop : No
Control Panel : No
My Network Places : No
Entire Network : No
Remote Computer : No
Filename : c:\PROGRA~1\mcafee\msc\MCCTXM~1.DLL
CLSID : {CCA9EFD3-29ED-430A-BA6D-E6BBFF0A60C2}
File Created Time : 2012-11-30 12:43:20
CLSID Modified Time: 2016-12-15 11:12:15
Microsoft : No
File Extensions : *, .lnk, Folder, lnkfile, opensearchfilefolderresult
File Attributes : A
File Size : 374,800
.NET Extension : No
Digital Signature :
Missing File : No
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possible duplicate of Windows Explorer Hangs on Right-Click
– Ƭᴇcʜιᴇ007 – 2014-07-21T15:03:20.047