1. Open file addcomments.tpl and focus in : class
<textarea name="comments" class="f_textarea" id="comments" >{text}
We have class : f_textarea
2. Open all .css file of current template and find f_textarea
Like this
.f_textarea {
color: #757575;
font-size: 11px;
font-family: tahoma;
background-image: url(../images/dlet_field_o.gif);
background-repeat: repeat-x;
width: 459px;
height: 156px;
border: 1px solid #e0e0e0;
color: #757575;
font-size: 11px;
font-family: tahoma;
background-image: url(../images/dlet_field_o.gif);
background-repeat: repeat-x;
width: 459px;
height: 156px;
border: 1px solid #e0e0e0;
We edit height
.f_textarea {
color: #757575;
font-size: 11px;
font-family: tahoma;
background-image: url(../images/dlet_field_o.gif);
background-repeat: repeat-x;
width: 459px;
min-height: 156px;
border: 1px solid #e0e0e0;
color: #757575;
font-size: 11px;
font-family: tahoma;
background-image: url(../images/dlet_field_o.gif);
background-repeat: repeat-x;
width: 459px;
min-height: 156px;
border: 1px solid #e0e0e0;
3. Open file addcomments.tpl
At top of this file, add
<script language="javascript">
function countLines(strtocount, cols) {
    var hard_lines = 0;
    var last = 0;
    while ( true ) {
        last = strtocount.indexOf("n", last+1);
        hard_lines ++;
        if ( last == -1 ) break;
        }
    var soft_lines = Math.ceil(strtocount.length / (cols-1));
    var hard = eval("hard_lines " + unescape(">") + "soft_lines;");
    if ( hard ) soft_lines = hard_lines;
    return soft_lines;
}
function cleanForm() {
    var the_form = document.getElementById('comments');
    the_form.rows = countLines(the_form.value,the_form.cols) +1;
    setTimeout("cleanForm();", 500);
}
cleanForm();
</script>
function countLines(strtocount, cols) {
    var hard_lines = 0;
    var last = 0;
    while ( true ) {
        last = strtocount.indexOf("n", last+1);
        hard_lines ++;
        if ( last == -1 ) break;
        }
    var soft_lines = Math.ceil(strtocount.length / (cols-1));
    var hard = eval("hard_lines " + unescape(">") + "soft_lines;");
    if ( hard ) soft_lines = hard_lines;
    return soft_lines;
}
function cleanForm() {
    var the_form = document.getElementById('comments');
    the_form.rows = countLines(the_form.value,the_form.cols) +1;
    setTimeout("cleanForm();", 500);
}
cleanForm();
</script>
Finish
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