X_FLAG_DUPLICATE
Means
two flags were declared with the same key
Typical cause
a copy-pasted defineFlag(), so one of the two declarations decides nothing
Fix
rename one of the two defineFlag({ key: '<key>' }) declarations
two flags were declared with the same key
a copy-pasted defineFlag(), so one of the two declarations decides nothing
rename one of the two defineFlag({ key: '<key>' }) declarations