The small size of textboxes and textareas in some websites/blogs makes it difficult to comment. This case can also occur while filling up an online application. We are unable to preview the complete contents in textareas/ boxes. Resizeable is an add-on for Firefox which does the job of resizing any HTML form fields including textareas, select boxes, text fields, and iframes.
After installation, you can re size HTML forms fields horizontally or vertically or combined together.
Download Resizeable Add-on