The issue
Once the first private message is deleted, the messages are no longer displayed.
Logs in /storage/logs is empty, the error does not generate logs.
The bug is also reproducible at https://nightly.flarum.site/

Flarum information
2.0beta3
PHP Warning: Module "zip" is already loaded in Unknown on line 0
Flarum core: 2.0.0-beta.3
PHP version: 8.2.7
MySQL version: 10.11.3-MariaDB-1+rpi1
Loaded extensions: Core, date, libxml, openssl, pcre, zlib, filter, hash, json, pcntl, random, Reflection, SPL, session, standard, sodium, zip, mysqlnd, PDO, xml, bz2, calendar, ctype, curl, dom, mbstring, FFI, fileinfo, ftp, gd, gettext, iconv, intl, exif, mcrypt, mysqli, pdo_mysql, Phar, posix, readline, shmop, SimpleXML, sockets, sysvmsg, sysvsem, sysvshm, tokenizer, xmlreader, xmlwriter, xsl, Zend OPcache
+--------------------------+---------------+--------+
| Flarum Extensions | | |
+--------------------------+---------------+--------+
| ID | Version | Commit |
+--------------------------+---------------+--------+
| flarum-flags | v2.0.0-beta.3 | |
| flarum-approval | v2.0.0-beta.3 | |
| flarum-tags | v2.0.0-beta.3 | |
| flarum-suspend | v2.0.0-beta.3 | |
| flarum-subscriptions | v2.0.0-beta.3 | |
| flarum-sticky | v2.0.0-beta.3 | |
| flarum-statistics | v2.0.0-beta.3 | |
| flarum-messages | v2.0.0-beta.3 | |
| flarum-mentions | v2.0.0-beta.3 | |
| flarum-markdown | v2.0.0-beta.3 | |
| flarum-lock | v2.0.0-beta.3 | |
| flarum-likes | v2.0.0-beta.3 | |
| flarum-lang-english | v2.0.0-beta.3 | |
| flarum-extension-manager | v2.0.0-beta.3 | |
| flarum-emoji | v2.0.0-beta.3 | |
| flarum-bbcode | v2.0.0-beta.3 | |
+--------------------------+---------------+--------+
Base URL: http://192.168.1.2/public
Installation path: /var/www/html
Queue driver: sync
Session driver: file
Mail driver: log
Debug mode: off