title: Is a textarea's cols attribute supposed to indicate 1 less than the number of columns?
body: <p>Every resource I can find says that a textarea's cols attribute indicates the number of average character widths in a horizontal line. Yet, in Chrome, Firefox, and Safari (all on OSX), setting a textarea's cols to (eg) 80, with a monospace font, will allow you to type 81 characters before it wraps. It's not a rounding issue; cols=1 adds the same amount. It's not a padding or margin issue either; behavior is the same with all style stripped. And it's only cols, not rows.</p>
  
  <p>Is this specified behavior? If so, why isn't it in the spec, or any of hundreds of online guides / resources? If it's an unofficial convention, is it reliable enough that I can always set cols=79 for 80 columns, instead of setting a css width?</p>