Add opt-in cross-source package deduplication - #6590

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Line matches candidate pattern (assign regex) `= /[^*].*?(?:[a-z]{3,}|[A-Z]{3,}|[A-Z][a-z]{2,}).*/[gi]?(?=\W|$)` (candidate-pattern)

Line matches candidate pattern (regex choice) `\(\?:[^)]+\|[^)]+\)` (candidate-pattern)