Feature: #87200 - Send plaintext and HTML mails in EmailFinisher¶
See Issue #87200
EmailFinisher of EXT:form now sends mails with a plaintext and an HTML part. A new option
addHtmlPart has been added to configure if a HTML part should be added to mails.
Mails now contain both plaintext and HTML parts to support a wider audience.
Enforcing a plaintext-only mail increases reception and security.