Copy / Paste doesn't work

I am using browser to access Horizon View 5.2 virtual desktops. I am also trying to configure Copy / Paste feature, but can't seem to make it work. Here is what I did sofar:

Create OU for the Virtual desktops. Create GPO, attached pcoip.adm template to this GPO and configured the following parameters:

• Computer Configuration-->Policies-->Administrative Template-->Classic Administrative Templates (ADM)-->Not Overridable Administrator Settings

             Configure clipboard redirection

                              Enabled in both directions

               Configure PCoIP virtual channels:

                              Disable all virtual channels other than mksvchan

Am I missing anything?

Thank you in advance,

Serge