Firstly, you don't need to reference $_ for the m// or the s///, as it is the default. Second, you can capture the bit you want in the m//. It's also better to use a different delimiter if you have /'s in your regex

push @array, $1 if m[^FOO\s=\s(.*?)/$];
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should capture everything after the first space after the '=' and before the trailing '/'. If the number of spaces might vary then

push @array, $1 if m[^FOO\s+=\s+(.*?)/$];
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This wouldn't harm if there is only one space before and after.

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