Update \Magento\Email\Model\Transport::setReturnPath to use the exist…

[TomashKhamlai]

Description (*)

An issue was identified where the Sender header is not following RFC 2822 while Symfony does follow

Update \Magento\Email\Model\Transport::setReturnPath to use the existing logic defined in Headers.php v6.4.19

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes Symfony\Component\Mime\Exception\LogicException: The "Sender" header must be an instance of "Symfony\Component\Mime\Header\MailboxHeader" (got "Symfony\Component\Mime\Header\MailboxListHeader") #39823

Manual testing scenarios (*)

1. Log in to your Magento Admin Panel.
2. Navigate to Stores.
3. Go to Configuration.
4. Select Advanced. In the left-hand sidebar, scroll down and click on "Advanced".
5. Choose System. Under the "Advanced" section, click on "System".
6. Expand Mail Sending Settings. On the "System" configuration page, expand the "Mail Sending Settings" section.
7. Locate the "Set Return Path" Option. Here, you will find the "Set Return Path" setting.

Questions or comments

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• README.md files for modified modules are updated and included in the pull request if any README.md predefined sections require an update
• All automated tests passed successfully (all builds are green)

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[TomashKhamlai]

@magento run Magento Health Index

[TomashKhamlai]

@magento run Static Tests

[TomashKhamlai]

@magento run all tests

[TomashKhamlai]

@magento run Unit Tests

[magento-automated-testing]

Failed to run the builds. Please try to re-run them later.

[TomashKhamlai]

@magento run Sample Data Tests CE

[magento-automated-testing]

Failed to run the builds. Please try to re-run them later.

[TomashKhamlai]

@magento run Sample Data Tests CE

[magento-automated-testing]

Failed to run the builds. Please try to re-run them later.

[TomashKhamlai]

Later, like in 2026?!

@magento you are hilarious! Stop dragging your feet and get the tests done!

[TomashKhamlai]

@magento run all tests