Remote +x

[MrIron-no]

• Allow U:lined servers to set umode +x remotely using OPMODE.
• Only permit ACCOUNT messages from U:lined servers.

[Ratler]

Is this really doing what you intend? If I get this right, your intent is "require CONF_UWORLD_OPER for +o/-o, but allow any U:line for +x."? But in he current form, I think it becomes overly permissive. If conf exists but the mode is not +o/-o (e.g. it's +x, or any arbitrary string like +w, -i, +Z), the CONF_UWORLD_OPER flag check is entirely bypassed. Any U:lined server (even one without the oper flag) can send +x, and any other unrecognized mode string silently falls through to return 0.

I don't think it would technically be an issue, but it might be cleaner to be explicit.

Something like, it also make it a bit less fragile for null check safety since you return immediately if conf is not set:

if (!conf)
    return send_reply(sptr, ERR_NOPRIVILEGES, parv[1]);

if ((!strcmp(parv[2], "+o") || !strcmp(parv[2], "-o")) && !(conf->flags & CONF_UWORLD_OPER))
    return send_reply(sptr, ERR_NOPRIVILEGES, parv[1]);