split CUTS your string into fields. Between the beginning of string and "WINGFRAME ", there is the empty string. Example

$ perl -e " print qq!($_)\n! for split /,/, q!,1,2,3!"
()
(1)
(2)
(3)

$ perl -e " print qq!($_)\n! for split /,/, q!,,,,1,2,3!"
()
()
()
()
(1)
(2)
(3)

$ perl -e " print qq!($_)\n! for split /(,)/, q!,,,,1,2,3!"
()
(,)
()
(,)
()
(,)
()
(,)
(1)
(,)
(2)
(,)
(3)
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There is an empty string around every corner

$ perl -e " print qq!($_)\n! for split /,/, q!5,,,!"
(5)

$ perl -e " print qq!($_)\n! for split /(,)/, q!5,,,!"
(5)
(,)
()
(,)
()
(,)
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