I tried forced-mode DoH in Firefox 68 and 69, on Debian 9 and 10. In all cases, it worked for a while then stopped to work after a few hours (at random it seems

I tried forced-mode DoH in Firefox 68 and 69, on Debian 9 and 10. In all cases, it worked for a while then stopped to work after a few hours (at random it seems). The only way for me to make it work again was to disable DoH. I guess a more long term solution is to have a local proxy dns-to-doh, but we are falling back in the solution that only a technical user can setup : https://developers.cloudflare.com/1.1.1.1/dns-over-https/cloudflared-proxy/ https://developers.cloudflare.com/1.1.1.1/dns-over-https/clo... https://facebookexperimental.github.io/doh-proxy/ https://facebookexperimental.github.io/doh-proxy/ And it means setting up firewall routing and filters, as some softwares don't have settings to add DNS proxy, or even bypass them (Google Chrome for example)