It doesn't show anything for my site either :( Life is difficult! (http://inst.eecs.berkeley.edu/~tikhon) And my page is fully standards compliant. (Yours might be as well--I didn't check.)
Although I can't speak for the OP, and you may be asking for a different reason, but double slashes are an acceptable way to write fully qualified URLs while still being protocol agnostic (that is to say, if you're on a page that was served via HTTPS, the double slash URL implies using the HTTPS protocol). It let's you have fully qualified URLs, without having to worry about the protocol and browser whining about mixed security.
Not working for me on Chrome on Mac. Keeps the HN url appended on top of my own url. When I manually edit, still doesn't work, just gives me the original form.
I can see why this would be very useful (instead of trawling through the CSS with dev tools or using a colourpicker)
- On closer inspection, it looks like it's always returning the colours for the first search I made, whichever that is..
(Chrome latest on Mac)