Using Identity EntityFrameworkCore in Entities library

I have 2 libraries in my project, these are:

• ProjectName.Data.Entities
• ProjectName.Data

Inside Entities project I have a User class defined like:

public class User : IdentityUser<int>
{
   public string FirstName { get; set; }
   public string LastName { get; set; }
}

In order to extend IdentityUser I need to add Microsoft.Identity.EntityFrameworkCore to the project however I feel like EntityFrameworkCore should only be added to the data layer. Putting it in the Entities layer feels like I'm not isolating layers good enough.

Is this bad design?