QtWebEngine: Object.defineProperty not using default values for property __proto__ on Object.prototype

We discovered a case where, when using the Object.defineProperty API in the Javascript environment, the expected default values are not always correct. The minimally reproducible snippet of Javascript that provokes this behavior is:

Object.defineProperty(Object.prototype, '__proto__', {get: () => ''}); 

After which, when inspecting the property _proto_ with Object.getOwnPropertyDescriptor(), it is listed as enumerable when it shouldn't.

This behavior only occurs when operating on the Object.prototype object from our testing.
When testing the same behavior on Qt 6.4.x and Qt 6.6.x this behavior does not occur.

Attached is a minimal example that reproduces the bug