web2.0goodies.com

If you are using nicEdit on content editable areas instead of the iFrame method, then you may have run across the FireFox bug that prevents you from changing the text alignment on the first line of a content editable element. 

As a work around, change the nicCommand method in nicEdit.js (Line 610 or so), to be this:

nicCommand : function(cmd, args) {
        if ((cmd == 'justifyright') || (cmd == 'justifyleft') || (cmd ==
        'justifycenter') || (cmd == 'justifyfull')) {
              try {
                 document.execCommand(cmd, false, null);
              }
              catch (e) {
                 //special case for Mozilla Bug #442186
                 if (e && e.result == 2147500037) {
                    //probably firefox bug 442186 - workaround
                    var range = window.getSelection().getRangeAt(0);
                    var dummy = document.createElement('div');

                     //To restore the range after collapsing for triple click bug...
                     var restoreSelection = false;
                    dummy.style.height="1px;";

                    //find node with contentEditable

                    //Triple Click selection Problem in mozilla, the selection contains the content editable div, which creates a problem for some reason, so we collapse the selection to the end, and then re-select everything...
                    if(range.startContainer.contentEditable == 'true'){
                        window.getSelection().collapseToEnd();
                        restoreSelection = true;
                    }

                    var ceNode = window.getSelection().getRangeAt(0).startContainer;

                    while (ceNode && ceNode.contentEditable != 'true')
                       ceNode = ceNode.parentNode;

                    if (!ceNode) throw 'Selected node is not editable!';

                    ceNode.insertBefore(dummy, ceNode.childNodes[0]);
                    document.execCommand(cmd, false, null);
                    dummy.parentNode.removeChild(dummy);

                     //RestoreSelection if we changed it...
                     if(restoreSelection){
                        window.getSelection().addRange(range);
                     }
                 } else if (console && console.log) console.log(e);
              }
           } else {
              document.execCommand(cmd, false, args);
      }
    }