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Showing content from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Cant_set_prototype below:

TypeError: can't set prototype of this object - JavaScript

TypeError: can't set prototype of this object

The JavaScript exception "can't set prototype of this object" occurs when attempting to set the prototype of an object, but the object's prototype is frozen, either by being a built-in immutable prototype object, or by being non-extensible.

Message

TypeError: Immutable prototype object 'Object.prototype' cannot have their prototype set (V8-based)
TypeError: #<Object> is not extensible (V8-based)
TypeError: can't set prototype of this object (Firefox)
TypeError: Cannot set prototype of immutable prototype object (Safari)
TypeError: Attempted to assign to readonly property. (Safari)

Error type What went wrong?

You are using one of the prototype-mutating methodsâmost notably, Object.setPrototypeOf()âon an object whose prototype is immutable. Some built-in objects have immutable prototypes, such as Object.prototype and window, for security reasons. User objects can also prevent prototype changes by using Object.preventExtensions(), Object.seal(), or Object.freeze().

Examples Changing the prototype of a built-in object

A selected few built-in objects have immutable prototypes. For example, you cannot change the prototype of Object.prototype:

Object.setPrototypeOf(Object.prototype, {});

This prevents you from being able to arbitrarily change the behavior of all objects in the system. The prototype of Object.prototype is always null. However, other built-in prototype objects, such as Function.prototype and Array.prototype, are not protected by default in this regard.

Changing the prototype of a non-extensible object

If you make an object non-extensible, you cannot change its prototype either:

const obj = {};
Object.preventExtensions(obj);
Object.setPrototypeOf(obj, {});
// TypeError: can't set prototype of this object