The background of the computed styles panel is currently set to transparent. It should actually be white.
Created attachment 255356 [details]
Comment on attachment 255356 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=255356&action=review
> + background-color: #fff;
Should be "white".
This is a regression from http://trac.webkit.org/changeset/185836 (sorry!).
Besides #fff/white, the patch looks fine to me.
Created attachment 255468 [details]
Comment on attachment 255468 [details]
Clearing flags on attachment: 255468
Committed r185913: <http://trac.webkit.org/changeset/185913>
All reviewed patches have been landed. Closing bug.