Hi,
I’ve looked it up, and it is possible, with a small custom CSS snippet:
[html]input:focus::-webkit-input-placeholder { color:transparent !important; }
input:focus:-moz-placeholder { color:transparent !important; }
input:focus::-moz-placeholder { color:transparent !important; }
input:focus:-ms-input-placeholder { color:transparent !important; }[/html]
Basically this will change the input placeholder texts color to transparent, whenever it’s focused.