wysihtml5-resize.js

this.editor = new wysihtml5.Editor("textarea");
this.editor.observe("load", function () {     
    var $iframe = $(this.composer.iframe);
    var $body = $(this.composer.element);
    
    $body
      .css({
        'min-height': 0,
        'line-height': '20px',
        'overflow': 'hidden',
      })
      .bind('keypress keyup keydown paste change focus blur', function(e) {
        var height = Math.min($body[0].scrollHeight, $body.height());
        // a little extra height to prevent spazzing out when creating newlines
        var extra = e.type == "blur" ? 0 : 20 ;
        $iframe.height(height + extra);
      });
});

Great piece of code. I've spend almost a day before finding this.

Do you have an idea how to perform the autoresize on load also? As it is now, the first resize does not happen until you click to activate the textarea.

Doesn't work with wysihtml5

Don't forget to set a default height on iframe body for it to work otherwise the scrollHeight is miscalculated.

awesome piece of code, thanx for sharing.