Messages with non latin charachters not showing properly

[alpapad]

Messages with non latin charachters not showing properly (ISO-8859-8-i)
Message attached. Shows ok in Outlook, used to work with version 3.1 . Fails in 3.15

0d6c567a-e520-4740-a449-9109a1ea477c.eml

[alpapad]

Same issue, UTF-7 this time. Again working in 3.1

95203115-b39e-4e8a-b431-ac098a9c3b26.eml

[alpapad]

Logs:

220 smtp4dev smtp4dev ready
EHLO smtp4dev
250-Nice to meet you.
250-8BITMIME
250-SIZE
250-SMTPUTF8
250-AUTH=CRAM-MD5 PLAIN LOGIN XOAUTH2
250 AUTH CRAM-MD5 PLAIN LOGIN XOAUTH2
MAIL FROM: AdeleV@feisar.solutions
250 New message started
RCPT TO: alex@koukou.com
250 Recipient accepted
DATA
354 End message with period
Received: from test-suite (test-suite) by smg.e2e (Postfix) with ESMTPS id
72FD91A538654CF79FE255BE51A24DFF for a@a; test
Date: Sat, 30 May 2026 00:54:05 +0300 (EEST)
From: AdeleV@feisar.solutions
To: alex@koukou.com
Message-ID: 18814418-ed25-4c43-b69d-8023448da969@email.mailgun.com
Subject: =?ISO-8859-8-i?B?8vjhIOjl4S4g7Ons5CDo5eEu4eX3+CDo5eE=?=
MIME-Version: 1.0
Content-Type: multipart/alternative;
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------=_Part_0_610435214.1780091645501-- . 250 Mail accepted QUIT 221 Goodbye

[alpapad]

AIs say this is missing:

    public static async Task Main(string[] args)
    {
        // Register encoding provider for legacy code pages (ISO-8859-8-i, ISO-8859-1, cp1252, etc.)
        // This must be done before any encoding operations occur
        Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
        
        // Enable UTF-7 encoding support for legacy email messages
        // Note: UTF-7 is considered unsafe and disabled by default in .NET for security reasons,
        // but some legacy email systems may still use it. This allows smtp4dev to handle such messages.
        AppContext.SetSwitch("System.Text.Encoding.Web.EnableUnsafeUTF7Encoding", true);
        System.Text.Encoding.RegisterProvider(System.Text.CodePagesEncodingProvider.Instance);

[alpapad]

A pr is here: #2109 Tested locally and it works.

Not my code though, AI generated