Special characters not supported in delimiter of json_lines codec

[conet]

According to the documentation of json_lines codec plugin 2 the default value of the delimiter option is newline (\n). However, when \n (or other unicode/special character like \x00) is explicitly defined in the input configuration of Logstash, it is considered to be a string containing of two characters:\ and n.

See this thread:
https://discuss.elastic.co/t/special-characters-not-supported-in-delimiter-of-json-lines-codec/114560

I encountered this around 5.2 and was surprised to see that it is still an issue in 6.4.2.

[conet]

I would like to use the plugin like this:

output {
    tcp {
	codec => json_lines { 
          delimiter => "\0"
        }
...
    }
}

But I end up with:

{...}\0{...}

instead of the actual \0 character, the same is true for any special characters.