I loved elastic textareas since the very first moment I used one (at facebook obviously). They let you save screen real estate while at the same time they are more comfortable for the end user. It’s one of the rare occasions when you can have your UI cake and eat it too!
However, I never liked the implementation of the feature. In case you never wondered how it’s done, let me explain it in a nutshell: All elastic textarea scripts (or at least all that I know of) create a hidden (actually, absolutely positioned and placed out of the browser window) div, copy some CSS properties from the textarea to it (usually padding, font-size, line-height, font-family, width and font-weight) and whenever the contents of the textarea change they copy them to the hidden div and measure it’s dimensions. It might be good enough for facebook, where the styling of those textareas is fairly simple and consistent throughout the site, or any other particular site, but as a generic solution? I never liked the idea. (more…)
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