I fancy that converting your code from

$stripped_html[$x] = join(" ",split " ",$stripped_html[$x]);
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to

$stripped_html[$x] = join(" ",split(/\s+/,$stripped_html[$x]));
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will do the trick. The reason being that if you have more than one white spaces, say, n, the split will generate n-1 undef's in the array, thus the warning.

Well, I would probably rewrite this using regular expression:

$stripped_html[$x] =~ s/\s+/ /g;
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