Citrix has released the Online Plug-in 12.1 for Windows
ICA File Signing. Helps protect users from unauthorized application or desktop launches by digitally signing .ICA files. You can configure the online plug-in security policy and digital-signing requirements using Group Policy Objects or the Citrix Merchandising Server with the online plug-in. The online plug-in verifies that a trusted source generated the application launch and based on administrative policy, protects against application launches from untrusted servers.
Enhanced printing performance. Improves user printing performance and speed when printing to redirected client printers. Install the XenApp Printing Optimization Pack on the server running XenApp 6 for Windows Server 2008 R2 and configure the server-side policy settings for:
Dynamic Client Printer Mapping. Redirected printers are discovered dynamically and created automatically.
Optimized EMF Universal Print Driver. Reduction in bandwidth consumption for the most demanding printing applications.
New decoder for HDX 3D Pro Graphics. A new deep compression codec is included in the online plug-in to receive 3D professional graphics over low bandwidths. For details about HDX 3D Pro Graphics, see http://support.citrix.com/article/CTX124443