Hi @nobodywasishere ,
Thanks for that. We actually happen to deploy filtering to a lot of our customers by way of DNS over HTTPS (which we've invested a lot of time in doing for iOS/iPadOS, Windows, and macOS devices through apps and configuration profiles). We enforce DNS resolution over a custom encrypted link installed for individual devices, or home Wi-Fi routers that support DNS over TLS. There are various ways that we guide our users to avoid workarounds, such as VPNs. We can block VPN apps on Android, and on Windows and macOS, our users are instructed to change the user account settings on PCs to prevent VPN apps from being used (where we also try to block their networking). On PCs, we automatically disable built-in DoH features for most web browsers (including Firefox) through enterprise policies as a precaution.
We've had a lot of success with enforcing Safe Search for our customers by way of a CNAME DNS record. We've taken advantage of Google, Bing, and DuckDuckGo all supporting CNAME DNS record settings. In addition, Qwant and Yandex support CNAME records, and Ecosia have just added support too.