When trying to make a new global script, doing a specific snmpwalk on a host for example:

snmpwalk -v2c -c public IP .1.3.xxxxxx

This works, but the moment the host is not listening on port 161, but on a different port, the snmpwalk command should be changed into:

snmpwalk -v2c -c public IP:PORT .1.3.xxxxxx 

So in Zabbix that would be something like:

snmpwalk -v2c -c public {HOST.CONN} .1.3.xxxxxx 

and for the custom port:

snmpwalk -v2c -c public {HOST.CONN}:{HOST.PORT} .1.3.xxxxxx 

According to the docs( https://www.zabbix.com/documentation/5.4/manual/appendix/macros/supported_by_location)

is supported in "→ Global scripts (including confirmation text)" but {HOST.PORT} is not, effectively limiting global scripts on all non default ports...

Please make {HOST.PORT} also available in Global scripts.