Frontend Interview experience at PayPal | Failed in Dream Interview

✅ Questioned on how JS Engine works?

✅ Implement a Nested File Explorer Component in React with the following requirements:

1. The component should maintain a hierarchical structure in the UI.
2. Each directory should persist its own expandable/collapsible state (just like VS Code).
3. Implement Create, Rename, and Delete options.

I messed up managing some states, making things hard and couldn’t fulfill the last requirement. 

✅ Asked a DSA Problem based on strings (Find All Anagrams in a String)

✅ Write a polyfill of Lodash’s Flatten Method with the levels parameter.

✅ More questions around the performance, memory leaks & React.