--do-0x20-encode, --no-0x20-encode

Dnsmasq can scramble the case of letters in DNS queries it sends upstream as a security feature. This technique can interact badly with rare broken DNS servers which don't preserve the case of the query in their reply. The first time a reply is returned which matches the query in all respects except case, a warning will be logged. If this coincides with DNS not functioning, it is necessary to disable the feature. As at version 2.91, 0x20 encoding is disabled by default, and must be enabled with --do-0x20-encode. The default may change in the future, so to be sure of its status after an upgrade, set --do-0x20-encode or --no-0x20-encode in your config. --no-0x20-encode overrides --do-x20-encode or a future default 0x20-encode enable.