Filtering / Grouping on dynamic properties does not translate to valid SQL (exception)

Assemblies affected
ASP.NET Core OData 8.0.11

Context
I'm using EF with PostgreSQL And have an entity that needs to support 'custom fields'. I followed
this guide from Microsoft and managed to get the following result for example:

{
    "@odata.context": "https://localhost:9001/v1/$metadata#Tickets",
    "value": [
        {
            "subject": "This is a test ticket.",
            "createdAt": "2022-08-31T11:25:07.206657Z",
            "updatedAt": "2022-09-03T20:29:19.836242Z",
            "id": "006ad14f-8f5e-b3aa-df9f-a193f9f34d6e",
            "language": "English"
        }
    ]
}

Describe the bug
When I try to filter or groupby on a dynamic property, I get the following exception:

The LINQ expression 
'DbSet<Ticket>().Where(t => (string)t.CustomFields.ContainsKey("language") ? t.CustomFields["language"] : null == __TypedProperty_0)' 
could not be translated. 
Additional information: Translation of method 'System.Collections.Generic.Dictionary<string, object>.ContainsKey' failed. If this method can be mapped to your custom function, see https://go.microsoft.com/fwlink/?linkid=2132413 for more information. 
Either rewrite the query in a form that can be translated, or switch to client evaluation explicitly by inserting a call to 'AsEnumerable', 'AsAsyncEnumerable', 'ToList', or 'ToListAsync'. See https://go.microsoft.com/fwlink/?linkid=2101038 for more information.

Entity Model

public class Ticket : WorkspaceEntity
{
    [Required]
    public string Subject { get; set; }

    public DateTime? CreatedAt { get; set; }

    public DateTime? UpdatedAt { get; set; }

    public Dictionary<string, object> CustomFields { get; set; }
}

EDM (CSDL) Model

<EntityType Name="Ticket" OpenType="true">
<Key>
<PropertyRef Name="id"/>
</Key>
<Property Name="subject" Type="Edm.String" Nullable="false"/>
<Property Name="createdAt" Type="Edm.DateTimeOffset"/>
<Property Name="updatedAt" Type="Edm.DateTimeOffset"/>
<Property Name="id" Type="Edm.Guid" Nullable="false"/>
</EntityType>

Request
GET https://localhost:9001/v1/tickets?$filter=language%20eq%20%27French%27

Response
See exception above.

Expected behavior
To get all tickets where language is equal to 'French'.

Screenshots
N/A