Explained elsewhere. It happens when images on the page from 3rd party sites are not on SSL, and browsers then inform you it's not 100% SSL... and browsers cache that info so that if the warning was on a redirect you'd still see it... hence once you've viewed one thread containing images, the strike-through remains until the end of the browsing session.
Explained elsewhere. It happens when images on the page from 3rd party sites are not on SSL, and browsers then inform you it's not 100% SSL... and browsers cache that info so that if the warning was on a redirect you'd still see it... hence once you've viewed one thread containing images, the strike-through remains until the end of the browsing session.