Steps to reproduce:

1. https://www.zabbix.com/documentation/7.0/en/manual/web_interface/frontend_sections/alerts/scripts
2. Read: 

   Script execution and result: The return value is limited to 16MB (including trailing whitespace that is truncated); database limits also apply. When data has to pass through Zabbix proxy, it must be stored in the database, thus subjecting it to the same database limits.

Result:
Output is limited with to 2k if exit code is not 0.

Expected:
Documentation should mention, that non-zero exit code will make error only 2k in size, instead of 16MB.