That depends a whole lot on what you want to achieve actually. Simplisticly you could use a regex to extract runs of uppercase letters. Something like:

my $runs = $str =~ /([A-Z]+)/g;
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But one of your strings looks like it ought have digits on the end so you may want to augment that to:

my $runs = $str =~ /([A-Z]+\d*)/g;
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That finds runs of upper case characters optionally followed by digits. But that may not be the end of the variations that you need to match so you may be better with a much fussier regex. For example:

my @runs = $str =~ /".*?\\([^\\"]*)"[^"]*"[^A-Z]*((?:(?! size).)+)/g;
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