Enforce safe search

Instructions for how to enforce safe search on all the search engines:

• https://support.google.com/websearch/answer/186669 (forcesafesearch.google.com)
• https://help.bing.microsoft.com/#apex/18/en-US/10003/0 (strict.bing.com)
• https://support.google.com/a/answer/6214622 (restrict.youtube.com)
• https://help.duckduckgo.com/duckduckgo-help-pages/features/safe-search/ (safe.duckduckgo.com)
• https://yandex.com/support/search/schoolsearch.html#schoolsearch (familysearch.yandex.ru)

<script src="https://gist.github.com/willsheppard/c38dd6643879b875d35707e367445b69.js"></script>

Other useful guides:

• https://protectyoungeyes.com/how-to-block-porn-on-any-device-for-free/
• https://docs.paloaltonetworks.com/pan-os/7-1/pan-os-admin/url-filtering/safe-search-enforcement
• https://support.opendns.com/hc/en-us/articles/227986807-How-to-Enforcing-Google-SafeSearch-YouTube-and-Bing
• https://support.opendns.com/hc/en-us/articles/228006487-FamilyShield-Router-Configuration-Instructions
• https://www.reddit.com/r/duckduckgo/comments/8qwzyl/feature_request_allow_network_operators_for_force/