Find computed style "source" ("trigger") in DOM inspector

Is it possible to find in DOM Inspector what tag/class/id combination triggered a particular Computed style rule. In my particular case I have a font that changes its appearance if a wrap the fragment in some other tag combination. So I see the different computed Style font-size(s), but can not quickly understand the difference开发者_如何学Go in the contexts. Maybe some other extension?

You'll want to look at the user agent CSS (check this in the Firebug "style" tab) instead of the computed styles. The user agent CSS is presented in order of inheritance, allowing you to scroll down the list to see which styles were overridden and by which other styles.