As a challenge I wanted to see how hard it would be to circumvent this. Here's a bookmarklet:
javascript:void(function(s,i){for(i=0;i<s.length;i++)if(window.getComputedStyle(s[i]).color=='transparent')s[i].style.display='none'}(document.getElementsByTagName('span')))
That should be one line with no spaces if gets line wrapped.