How to force Firefox to render textarea padding the same as in a div?

Question

I\'m attempting to provide a consistent width per line in pixels inside of a textarea across IE8, Firefox and Safari, so that text content wraps lines as predictably and con

Answer 1

Wow, I don't know the answer yet but I did try some stuff, and it appears as though a textarea, when you apply borders, margins and padding to it, doesn't change its width but puts the borders etc. on the inside. Try this:

.testbox {
    padding: 10;
    margin: 10;
    border: 5px solid black;
    background: red;
    width: 40px;
    height: 40px;
    font-size: 12px;
    line-height: 16px;
}

You could work around this by using something like this:

css:

.testbox {
    padding: 0;
    margin: 0;
    border: 0;
    background: red;
    width: 40px;
    height: 40px;
    font-size: 12px;
    line-height: 16px;
}

.testarea {
    padding: 0;
    margin: 0 -1px;
    border: 0;
    background: red;
    width: 100%;
    height: 100%;
    font-size: 12px;
    line-height: 16px;
}

This also seems to work in IE, except for the -1px, which throws the layout off (by one).