[BUG] Problem with encoding

[tito10047]

Environment (please complete the following information):

• PHP IMAP version: 4.1.0
• PHP Version: 7.2.7
• Type of execution: CLI

Describe the bug
I received some unknown encoding from $mail->textHtml . After received text I want to use in preg_replace and output is null
In version 3.1.0 was everything ok, today I switch to 4.1.0 and I have this problem

To Reproduce
email is in attachment

The used code:

$emailBody = $mail->textHtml;
$emailBody = preg_replace('~<style(.*?)</style>~umsi', "", $emailBody);

The headers of the parsed email, if required and possible (only, if it's NOT confidential):

Subject: test
Thread-Topic: test
Thread-Index: AQHW6OQF024C5Wt1Mk2B/tHD6Yarhw==
Date: Tue, 12 Jan 2021 13:08:29 +0000
Message-Id: <cd25dec5b47c4586a1d9178924a067a6@dsidata.sk>
Accept-Language: cs-CZ, sk-SK, en-US
Content-Language: cs-CZ
X-MS-Exchange-Organization-SCL: -1
X-MS-TNEF-Correlator: <cd25dec5b47c4586a1d9178924a067a6@dsidata.sk>
X-MS-Exchange-Organization-MessageDirectionality: Originating
X-MS-Exchange-Organization-AuthAs: Internal
X-MS-Exchange-Organization-AuthMechanism: 04
X-MS-Exchange-Organization-Network-Message-Id: 086d3ed1-3422-4529-2f74-08d8b6fb2826
X-MS-Exchange-Transport-EndToEndLatency: 00:00:00.2162177
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline
...

test-email.zip

[Sebbo94BY]

Can you still reproduce this issue in the release 4.3.0?

[Sebbo94BY]

I've just released a new version 4.5.3 with some more improvements regarding these encoding issues and some unit tests.

Relates to #657.

Feel free to reopen this issue, if you should be still able to reproduce your issue(s) or just open a new ticket.