Cannot open an .mbox file with neomutt (although it works with mutt)

Cannot open an .mbox file with mutt I want to open a 10GB .mbox file that I downloaded from my gmail account. When I use the command

neomutt -f 10GB_mboxfile.mbox

neomutt takes 10-20 seconds to open and when finally opened, there is no file listed in the the application. I have the following dummy .mbox (which I modified from a gmail mbox file):

From 9999999999999999@xxx Tue Mar 09 17:00:00 +0500 2019  
X-GM-THRID: 99999999999999999
X-mail-Labels: Archived,Sent,Opened
MIME-Version: 1.0
Date: Tue, 09 Mar 2019 17:00:00 +0500
Message-ID: 
Subject: THETITLE
From: My Name 
To: destination@mail.com
Content-Type: multipart/alternative; boundary="0000000000009999999999999"

--0000000000009999999999999
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable


ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ da=
s ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

--0000000000009999999999999
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ=
ZZ das ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ=
>

--0000000000009999999999999--

I am trying to open it with neomutt as follows:

neomutt -f themboxfile.mbox

neomutt opens but then no message is listed in the app. How is it possible to open this file with neomutt? (Although opening the same file works with mutt...) **EDIT** Beside the answer below I had a too old version: the apt get install neomutt on Ubuntu LTS 22.04 installed the version 20211029. I uninstalled neomutt and re-installed it with nix package manager. it installed NeoMutt 20231221 which worked without problem.