I have an object that's mapped to an entity as Embedded in Skipper. It's been working well, and previously it had a single field marked as unique, which worked ok as it was defined in the #[ORM\Column] attribute itself. Now I needed to add a new column and make it a compound unique constraint with two fields. Export from Skipper generated the correct #[ORM\UniqueConstraint(...)] in the same class where the #[ORM\Embeddable] attribute is, but the problem is that Doctrine doesn't support it. I think it should be defined on the main entity itself. And in Skipper, I can't create it there as the UI for selecting fields does not include the embedded fields...
So, a fix would be to either allow selecting embedded fields when defining indexes for an entity in the Skipper UI, or generate the indexes defined in an embedded object directly on the parent entities.