If you are using any custom DNS services such as NextDNS in your case, we cannot guarantee the stability and security of your connection, since your DNS queries are getting resolved by said custom DNS servers. This means that when you are connected to ProtonVPN, your DNS queries through our encrypted VPN tunnel. Please note that each Proton VPN server runs a DNS server as well, and our native apps have a default DNS leak protection feature that forces your internet connection to resolve DNS queries via our DNS servers. However, YouTube ads are served over the same domains that are needed to power the whole platform and for this reason, they can't be filtered out by our NetShield feature which is based on blocking/filtering domains that serve such ads. If you enable ad blocking in NetShield, not only will it protect you from malware, but it will also block the annoying ads that clutter your screen.

If it finds the domain of the website/service you are trying to visit or any of its components (scripts, images, etc.) on one of these lists, NetShield will automatically block it from loading. When NetShield is enabled, any time you try to go to a website or access a certain app/service, the Proton VPN app will check that website’s address/service/application against a massive database of sites known to host ads, trackers, malware, spyware, or any other malicious software.

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