Event Confirmation emails not working as expected with 5.29.1
Overview
Default system workflow messages for event registration confirmation emails are rendering incorrectly when viewed by recipients in a range of mail clients.
I recently upgraded a site from 5.24.4 to 5.29.1 and immediately noticed problems with some of the system workflow messages, specifically:
- Events - Registration Confirmation and Receipt (off-line)
- Events - Registration Confirmation and Receipt (on-line)
Both were using customised versions of the template but the customisations were minimal so I reverted to the defaults in both cases, but issues persist.
Current behaviour
When registering an event participant for a fee-free event via the admin interface an event confirmation email is sent. When viewed in an email client this email displays the plain text content of the message, and then underneath this the raw source for the HTML formatted content is shown. The client is configured to show HTML formatted content by default.
Where the event is chargeable we're seeing various manifestations of the event confirmation email. In some cases the email renders as I would expect, displaying the HTML formatted content, and with a PDF of the invoice attached (we have Tax and Invoicing enabled).
In others, the email renders as an empty email (no content displayed), but with an attachment called 'Mail Attachment'.
We're also seeing some of these emails rendering plain text first, then HTML formatted content (rendering correctly), but with no attached invoice PDF.
Expected behaviour
The expected behaviour is that the event confirmation emails should be consistent regardless of whether the event has a fee option or not. In an email client that is set to show HTML formatted content by default, HTML content should be shown, plain text content should not be displayed.
I'm reviewing the invoice template which is of course customised, and seeking to merge that with the current default, but an initial review of that template indicated relatively minimal changes. I'm also shortly to update CiviCRM to 5.30 in case that resolves any of these issues.
Environment information
- Browser: n/a
- CiviCRM: 5.29.1
- PHP: 7.3_
- CMS: Drupal 7.73
- Database: MariaDB 10.4
- Web Server: Apache 2.4