Why did the Supreme Court uphold the Assam Accords-based Section 6A of Citizenship Act? | Explained

What does the contentious provision stipulate? What are the court’s findings? What are the potential implications?

Why did the Supreme Court uphold the Assam Accords-based Section 6A of Citizenship Act? | Explained
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What does the contentious provision stipulate? What are the court’s findings? What are the potential implications?