TS2531 — Object Is Possibly Null

What causes this error

When strictNullChecks is enabled, TypeScript tracks nullability. DOM methods like getElementById and querySelector return nullable types. Optional chaining and function returns can also produce nullable values.

How to fix it

Add a null check before using the value. Use the non-null assertion operator (!) if you are certain the value exists. Use optional chaining (?.) for safe property access. Provide a fallback value with the nullish coalescing operator (??).

const el = document.getElementById('x');
el.textContent = 'hi';