F# LiteDB [<BsonIgnore>] is Ignored? - f#

Question

Context: Running F# in a containerized environment
$ dotnet --version 2.2.203
$ uname -a
Linux SAFE 4.15.0-48-generic #51-Ubuntu SMP Wed Apr 3 08:28:49 UTC 2019 x86_64 GNU/Linux
on Ubuntu 18.04 desktop machine.
This simple code ignores the [<BsonIgnore>] attribute. The value of Ignore is stored in LiteDB. Am I doing something wrong?
I've checked it by looking with the console command $ dotnet LiteDB.Shell.dll micompany.db:
...
> open micompany.db
> db.computers.find
[1]: {"_id":11,"Ignore":"ignore","Manufacturer":"Computers Inc.","Disks":[{"SizeGb":100},{"SizeGb":250},{"SizeGb":500}]}
This is the code:
open System
open LiteDB
open LiteDB.FSharp
[<StructuredFormatDisplay("{SizeGb}GB")>]
[<CLIMutable>]
type Disk =
{ SizeGb : int }
[<StructuredFormatDisplay("Computer #{Id}: {Manufacturer}/{Disks}")>]
[<CLIMutable>]
type Computer =
{ Id: int
[<BsonIgnore>] Ignore : string
Manufacturer: string
Disks: Disk list }
[<EntryPoint>]
let main argv =
let myPc =
{ Id = 0
Ignore = "ignore"
Manufacturer = "Computers Inc."
Disks =
[ { SizeGb = 100 }
{ SizeGb = 250 }
{ SizeGb = 500 } ] }
let mapper = FSharpBsonMapper()
use db = new LiteDatabase("micompany.db", mapper)
let computers = db.GetCollection<Computer>("computers")
// Insert & Print
computers.Insert(myPc) |> ignore
printfn "%A" myPc
0 // return an integer exit code
On the other hand, the [<StructuredFormatDisplay>] attribute of the Disk record is not correctly written (only a few dots appear in the console), when the Computer record is printed with printfn "%A" myPc. The output is:
Computer #12: Computers Inc./[...GB; ...GB; ...GB]
Is there anything else I need to say?