Hey!

I see that this is your first PR. That is great! Welcome!

Symfony has a contribution guide which I suggest you to read.

In short:

• Always add tests
• Keep backward compatibility (see https://symfony.com/bc).
• Bug fixes must be submitted against the lowest maintained branch where they apply (see https://symfony.com/releases)
• Features and deprecations must be submitted against the 6.4 branch.

Review the GitHub status checks of your pull request and try to solve the reported issues. If some tests are failing, try to see if they are failing because of this change.

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I am going to sit back now and wait for the reviews.

Cheers!

Carsonbot

Hey!

Thanks for your PR. You are targeting branch "6.4" but it seems your PR description refers to branch "6.4 for bug fixes".
Could you update the PR description or change target branch? This helps core maintainers a lot.

Cheers!

Carsonbot

Thank you @Romanavr.

It seems like this change is causing issues for me, when sending mails to Gmail accounts via Mailgun.
I am getting errors like the following in Mailgun:

5.7.1 This message is not RFC 5322 compliant. There are multiple Sender\n5.7.1 headers. To reduce the amount of spam sent to Gmail, this message has\n5.7.1 been blocked.

After some digging, it seems my sent message contains 2 sender headers, one capitalized and one not:

Sender: mail@example.com
sender: mail@example.com

I am still trying to figure out where the capitalized "Sender" header gets added in my flow, but haven't pinned that down yet.
However I'd like to point this issue out, for people encountering the same problem.
If I have more information that is relevant, I will update here.

I am not familiar enough with email headers, but if it is considered best practice to capitalize them, then maybe the custom header added via this change should also be capitalized?

It seems like this change is causing issues for me, when sending mails to Gmail accounts via Mailgun. I am getting errors like the following in Mailgun:

5.7.1 This message is not RFC 5322 compliant. There are multiple Sender\n5.7.1 headers. To reduce the amount of spam sent to Gmail, this message has\n5.7.1 been blocked.

After some digging, it seems my sent message contains 2 sender headers, one capitalized and one not:

Sender: mail@example.com
sender: mail@example.com

I am still trying to figure out where the capitalized "Sender" header gets added in my flow, but haven't pinned that down yet. However I'd like to point this issue out, for people encountering the same problem. If I have more information that is relevant, I will update here.

I am not familiar enough with email headers, but if it is considered best practice to capitalize them, then maybe the custom header added via this change should also be capitalized?

I just tested - everything is ok for me, what transport type are you using? API?

@Romanavr yes API.

@Romanavr yes API.

I was able to reproduce. Indeed, good point about capitalize the header.

@svendecabooter Please try 52017#fix and let me know if it works for you

Hello,

I have come across a problem caused by this change.

The header h:Sender is added here as UnstructuredHeader.

When it is added into payload here, sometimes it encodes incorrectly

The issue occurs only in some cases when using Sender Address with name part with diacritics, because of the difference in encoding of UnstructuredHeader and MailboxHeader.

example:

$unstructuredHeader = new UnstructuredHeader('From', '"Klaudie Šulcová" <foo@bar.com>');
$mailboxHeader = new MailboxHeader('From', new Address('foo@bar.com', 'Klaudie Šulcová'));

$unstructuredHeader->getBodyAsString(),  // ""Klaudie =?utf-8?Q?=C5=A0ulcov=C3=A1=22?= <foo@bar.com>"
$mailboxHeader->getBodyAsString()           // "Klaudie =?utf-8?Q?=C5=A0ulcov=C3=A1?= <foo@bar.com>"

I discovered this problem because some mailservers complained about the Sender header being invalid.

A simple solution to fix this problem would be adding the h:Sender header as MailboxHeader here

$headers->addMailboxHeader('h:Sender', $envelope->getSender());

I'll send a PR