This article applies to:

• R3000
• Web Filter (WF, WFR)

Question:

• Can Web Filter enforce safe-search for SSL-based Google search and Youtube in invisible mode?

Information:

No, the filter cannot enforce safe-search for Google search or YouTube in invisible mode.  You can read more about why in article Q13898.  

Workaround

There is a DNS workaround that can be put into place.  You can read the official answer from Google here under option 3.

To enforce safe search, update the DNS configuration for your network. Set the DNS entries for www.google.com and any other Google ccTLD subdomains to a CNAME entry for forcesafesearch.google.com  This will enforce encrypted safe-search on your entire network for any Google searches.

A similar process can be followed to enforce Safety Mode for videos on YouTube.  To enforce Safety Mode on Youtube set the DNS entries for www.youtube.com and any other Google ccTLD subdomains to a CNAME entry for forcesafesearch.google.com.  This will enforce Safety Mode for YouTube videos.