my $url = <ARGV>;
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Why change STDIN to ARGV?    And either way you still have to chomp the value received.

while ($new_videoURL) {
    chomp;
    print $new_videoURL ;
}
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Does $new_videoURL assign a value to $_?    And if not then why are you chomping the $_ variable?    And if the value in $new_videoURL doesn't change inside the loop then why are you using a loop at all?