Sender not added as MailboxHeader but is valid Address

maxwellkeeble → changed the visibility of the branch 1.0.x to hidden.

I wonder if this is related to https://www.drupal.org/i/3390183 →

I encountered it too, because webform reuses the From-header as Sender, and that often is Mailbox-format and not a simple address.

Attached is a patch that closely resembels yours. I skipped the email validation as Address will validate it as well and used a more general exception, as you might also get RfcComplianceException or LogicException.

It works in my case.

This issue has come up multiple times for various address headers. For example, I think I fixed it for Bcc and Cc headers back in this commit: https://git.drupalcode.org/project/symfony_mailer_lite/-/commit/e6921d96...

I just reworked the code in the MR to use the functionality I added there for all mailbox and mailbox list headers.

@maxwellkeeble and @interX, can you test my new version from the MR and see if it fixes the specific issues you were having?

Automatically closed - issue fixed for 2 weeks with no activity.