Web Scenario - Macro for http proxy

The http proxy setting in a Web Scenario template has to be set manually (only supports user or template macros).
It should be possibile to set it by a global macro (es: HOST.IP or HOST.DNS).

For instance, in a split-dns corp. environmento we have to check the reachability of a site (www.something.com) through different zabbix proxies, each using a specific http proxy .

We already have a ICMP check to the http proxy, It could be useful to add a Web Scenario to check www.something.com through the same http proxy, using the

macro (without touching dns configs, host files etc).