Did you recently get on and "catch up?" The way I understand it (which may not be correct,) if you ignore the thread for awhile, it stops sending you notifications. Once you catch up, the notifications start up again.
His weren't weak or flaky. On the contrary, they were rock hard and strong. The issue was the pronounced vertical stripes typical of the breed. They camouflaged some minute surface cracks on the damaged hoof. Our farrier was concerned that they would deepen to full-blown cracks if they chipped...