Question

And last month, a former employee accused the company of unethical behaviour. Frances Haugen released a cache of internal documents which she said showed Facebook had put profit before user safety.
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What is 'a cache of' internal documents'?

Answer 1

If you look up the meaning of "cache," you'll understand it perfectly!
www.merriam-webster.com/dictionary/cache

Clearly, the higher-ups at Facebook didn't want these documents to ever be made public knowledge.