Array property with object items not loaded correctly

[leanil]

Steps to reproduce

Define a model with an array property, where the item type contains a buffer.

@model()
export class DemoModel extends Entity {
  @property.array(Item)
  items: Item[];
}

@model()
export class Item extends Model {
  @property()
  buffer: Buffer;
}

Store and load an instance of this model.

await this.demoModelRepository.create({items: [{buffer: Buffer.from('data')}]});
const demo = await this.demoModelRepository.findOne();
console.log(demo?.items[0].buffer.toString())

Current Behavior

Prints nothing. The buffer in the loaded object is empty.

Expected Behavior

Prints "data".

Link to reproduction sandbox

https://github.com/leanil/array-prop-bug
(Just npm start it, the observer performs the test on start.)

Additional information

linux x64 16.17.0

├── @loopback/[email protected]
├── @loopback/[email protected]
├── @loopback/[email protected]
├── @loopback/[email protected]
├── @loopback/[email protected]
├── @loopback/[email protected]
├── [email protected]

Behaves the same way with 7.0.0-alpha.1.
The absence of an array case around here seems suspicious to me.