Static URL Web Filter stopped working (after no other changes?)

I have a FortiGate 100D running 5.6.  I have a policy which has been blocking certain static URLs for one of my kids, which was working beautifully up until about 2 weeks ago.  I've made no other configuration changes which would explain the behavior, and I've even restored a known good configuration from before the last date I know it worked.  I don't have current licenses (this is a home environment) but this has been the case for some time and according to Fortinet this feature should not be a licensing issue anyway.

I see the traffic that should be blocked, and it is being allowed by the same policy (presumably because the other criteria matches, but the Web Filter block is not working.)

Any ideas?