Even if you don't look at the computed styles, the user agent styles are shown in the default element style view, at least in Firefox. There, you can see all of the applied styles as a stack, so you can see which styles have been applied first, which ones have been overridden, etc.
This is a good place to look if you're trying to figure out why an element is behaving weirdly, because it shows all the styles and exactly how they override each other, as well as the source of each style.
This is a good place to look if you're trying to figure out why an element is behaving weirdly, because it shows all the styles and exactly how they override each other, as well as the source of each style.