There's no reason to use -0777 in that example.

perl -0777 -ne'print' in.txt
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and

perl -ne'print' in.txt
[download]

produce the same output. The difference is the former only loops once since it loaded the entire file into memory at once. The latter reads and prints a line at a time.

You can see the difference in the following:

perl -0777 -nle'print "[[[$_]]]"' in.txt
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and

perl -nle'print "[[[$_]]]"' in.txt
[download]