What will this code output? Spot the bug.
Difficulty: Hard😤

for (var i = 0; i < 5; i++) {
    setTimeout(function() {
        console.log(i);
    }, 1000);
}

JavaScript Task
Check that this string consists of numbers only.
Difficulty: Easy😁

string = "1234567890"

📝 CSS display: contents

How can display: contents improve layout flexibility? This property makes elements "transparent" in the DOM, merging their children with the parent container without altering visual display. It helps eliminate unnecessary wrappers and simplifies styling, but be aware of accessibility issues with screen readers.

The developer gets angry at the tester for finding yet another bug.🤣

How can the code be modified to handle both successful and failed promises?
Difficulty: Impossible😈

const promises = [
  Promise.resolve(1),
  Promise.reject(new Error('Error'))
];

Promise.all(promises)
  .then(results => console.log(results))
  .catch(error => console.error(error));

Find the error in the code.
Difficulty: Easy😁

function add(a, b) {
  return a + b;
}

const result = add(5);  
console.log(result);