< style >
#wrapper {
 width:1000px;
}

#block-one {
 width:60%;
}

#block-two {
 width:40%;
}
< /style >

< div id="wrapper" >
    < div id="block-one" >< /div >
    < div id="block-two" >< /div >
< /div >

Well, I recently noticed it while making a site for one of my clients. You know when you're structuring the front-end output to be more organized and you use tabs to space it on the doc? The problem is that Firefox recognize these structuring tabs as a space which leads to breaking the page and the only way around it is to not structure your front-end output, which then produce a very unorganized code - which ultimately makes it difficult to maintain. Will this be fix any time in the near future? I know that even if it will be fixed, this will still exist in older versions of Firefox so I still wont be able to structure it the way I need to. This usually happens for grids and certain elements, in the condition they are positioned inside a container like the below example: <pre><nowiki> < style > #wrapper { width:1000px; } #block-one { width:60%; } #block-two { width:40%; } < /style > < div id="wrapper" > < div id="block-one" >< /div > < div id="block-two" >< /div > < /div ></nowiki></pre> ---------------------------------------------------------------------------------- When child elements expected to use the entire space of the parent, the spaces are noticed more and because of those spaces - the child elements breaks as if #block-one is say width 61%, then #block-two (40%) is too big to fit there so it will be displayed below #block-one. Not sure I explained it in an understandable way but hope you got what I'm trying to say.