Using Simplenews, when I send a newsletter issue that has an image in it, the src attribute gets sent as a wrong URL. Instead of https://example.com/files/image/123.jpg, it gets sent as https://files/image/123.jpg. Of course, this fails. If I switch to using Mailchimp as an SMTP sender, it works fine.
Install simplenews, swiftmailer, and this app. Try it.
I am at a loss to track down the problem. The workaround is SMTP, but not as satisfying.
Closed: works as designed
1.0
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
Like you discovered yourself, the problem lies with the text format that's being used to filter the HTML of your mails. Either disable that option for the full_html text format, but that might impact other parts of your site, or configure a new text format without that option enabled for use with Mailchimp Transactional.
