Is this what you want??? 
use strict;
use warnings;
use 5.012;

use Text::Balanced qw( 
    extract_tagged 
    extract_multiple 
);


my $text = <<'END_OF_STRING';
{{Infobox
 text text text
 {{text text text
 text {{text text}}
 text}}
 {{{text {{text }}
    text }}}
}}
blah blah
blah blah
blah blah
{{Infobox
 text1 text1 text1 
 {{text1 text1 text1 
 text1 {{text1 text1}}
 text1}} 
 {{{text1 {{text1 }}
    text1 }}}
}}
{{Infobox one}}
END_OF_STRING

my @infoboxes = extract_multiple( $text, [ \&my_extractor], undef, 1 )
+;

sub my_extractor {
    extract_tagged(
        $text,
        "{{",
        "}}",
     );
}

for my $infobox (@infoboxes) {
    say $infobox;
    say '*' x 20;
}


--output:--
{{Infobox
 text text text
 {{text text text
 text {{text text}}
 text}}
 {{{text {{text }}
    text }}}
}}
********************
{{Infobox
 text1 text1 text1 
 {{text1 text1 text1 
 text1 {{text1 text1}}
 text1}} 
 {{{text1 {{text1 }}
    text1 }}}
}}
********************
{{Infobox one}}
********************

[download]

Here's the same result using regexes via Regexp::Common:

use strict;
use warnings;
use 5.012;

use Regexp::Common qw( balanced );


my $text = <<'END_OF_STRING';
{{Infobox
 text text text
 {{text text text
 text {{text text}}
 text}}
 {{{text {{text }}
    text }}}
}}
blah blah
blah blah
blah blah
{{Infobox
 text1 text1 text1 
 {{text1 text1 text1 
 text1 {{text1 text1}}
 text1}} 
 {{{text1 {{text1 }}
    text1 }}}
}}
{{Infobox one}}
END_OF_STRING



my $pattern = $RE{ balanced        }
                 { -begin => '{{'  }
                 { -end   => '}}'  };


while ($text =~ /($pattern)/gxms) {
    say $1;
    say '*' x 20;
}

--output:--
{{Infobox
 text text text
 {{text text text
 text {{text text}}
 text}}
 {{{text {{text }}
    text }}}
}}
********************
{{Infobox
 text1 text1 text1 
 {{text1 text1 text1 
 text1 {{text1 text1}}
 text1}} 
 {{{text1 {{text1 }}
    text1 }}}
}}
********************
{{Infobox one}}
********************

[download]

In reply to Re: RegEx - Positive Look-ahead by 7stud
in thread RegEx - Positive Look-ahead by tmharish

Title:
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