Ok it was Params::Validate. A fresh reinstall fixed the issue.

I still would like to know how to better debug this issue.

print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});

In reply to Re^2: script fails but succeeds in debugger by codeacrobat
in thread script fails but succeeds in debugger by codeacrobat

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