Does CSSOM block page rendering? Why?
Middle+
191
Frontend
6261
681
Describe the critical rendering path of the browser: from entering the URL in the address bar to rendering the page. Talk about DNS, TCP, HTTP, DOM construction, CSSOM, Render Tree, Layout, and Paint.
Middle+
188
What are reflow and repaint? What is forced reflow? How can rendering be optimized to reduce the number of forced reflows?
Middle+
157
In which cases does a component re-render in React? Tell us about reconciliation.
Middle+
149
How to make the makeBook function return expected values 0 and 5 instead of two dozens?
Middle+
148
How can you solve a problem that inheritance solves in an alternative way? What is composition in the context of TypeScript and React?
Middle+
146
Look at the makeBook function. Determine what will be printed to the console on lines 20-21 (the two commented lines). Explain the behavior of the function.
Middle+
126
What design patterns and code quality principles do you use when developing with React/TypeScript? How do you apply SOLID principles in frontend development?
Middle+
123
Refactor the component that renders a random number (from Promise) and the scroll position. Find the issues and fix them.
Middle+
118
What is HOC (Higher-Order Components)? What are they used for? Provide examples of using HOC in React.
Middle+
110
What are generics used for in TypeScript? How to restrict generics with specific types? What is type narrowing and how is it implemented?
Middle+
108
How does the Virtual DOM work in React? How does React determine the order of operations during re-rendering? Tell us about React Fiber and the scheduler.
Middle+
86
What is CORS? How does it work? What is the difference between simple requests (GET, POST) and preflight requests (OPTIONS)? What does CORS look at when sending a request?
Middle+
84