An easy way to get a start is by converting your Curl command to a Perl program using (my) Curl to Perl converter:
my $ua = LWP::UserAgent->new( 'send_te' => '0' );
my $r = HTTP::Request->new(
'GET' => 'https://example.com/',
'Accept' => '*/*',
'User-Agent' => 'curl/7.55.1',
'Cookie' => 'session=536...035a'
my $res = $ua->request( $r, ':content_file' => 'HTML_output.txt' );
Created from curl command line
curl https://example.com --cookie "session=536...035a" -o "HTML_output
I'm not sure if your Firefox stores its cookies in a cookies.txt file still or if it stores them in an SQLite database nowadays.
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Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link
or How to display code and escape characters
are good places to start.