By this you mean the chatfrane fading in and out when you hover over it. Prat does let you change this, but I would be remiss if I said that it was really much of a feature. To control this, you set the chatframes to have an alpha value of >0.5 using the default ui. Then they'll never fade in/out.
Prat has an easy way for you to set the variable that controls the threshold at which the fade occurs.
Frame module, chat frame alpha, set to 0.
Ah, sorry about that. Did not realize that the frame module had the chat frame hover transparency control. That's exactly what I needed, thanks for your help!