Web Dynpro CSS

Hi Guys,

I want to supply my own custom Web Dynpro CSS by putting the sap-css parameter in the Application Parameter in Web Dynpro iView property. From what I read in the forum, I need to change the "Supply Portal Stylesheet" parameter from "Yes" to "No" (so that the app does not read the portal theme). However, when I am trying to set the "Supply Portal Stylesheet" from "Yes" to "No", then save, the parameter value get reverted back automatically to "Yes". Has anyone ever experienced this issue?

Thanks,

Johannes