Hi, See IndentAppender in https://metacpan.org/pod/Log::Log4perl::FAQ#How-can-I-access-a-custom-appender-defined-in-the-configuration? and

    %m{chomp} Log message, stripped off a trailing newline
    %m{indent} Log message, multi-lines indented so they line up with 
+first
    %m{indent=n} Log message, multi-lines indented by n spaces
[download]