webpage development width and height attributes in IE

As webpage developers we know about and commonly use the width and height attributes to change the layout of our pages. But here is a not very known fact that I just came across, IE or Internet Explorer atleast since IE 8 supports not only whole numbers but decimals as well in the attribute. It doesn't seem that Firefox or any other browser will support this but for example if we have width="99.9%"

IE will return the extra .9% thus typing width="99.9%" will display different than typing width="99%"

however if using a browser such as Firefox if you have width="99.9%" it will render the page or element at 99% leaving out the extra 0.9% that we added

This could be useful in some way for small adjustments on your css but is best used in CSS when you have a different css file loaded based on the detected browser.