It seems that it does:
https://bugzilla.mozilla.org/show_bug.cgi?id=1544233
https://github.com/StevenBlack/hosts/issues/968
https://old.reddit.com/r/firefox/comments/e64073/dns_over_ht...
https://www.liquidweb.com/help-docs/Fixing-Firefox-Bypassing...
https://superuser.com/questions/437649/firefox-not-taking-no...
https://stackoverflow.com/questions/37452361/why-is-my-hosts...