Partial fix for broken tokens in event confirmation email

[MegaphoneJon]

Overview

See https://lab.civicrm.org/dev/core/-/issues/5676.

Before

The email confirmation text gets curly braces within URLs converted to URL encoding, breaking tokens. This happens on a) the Manage Event » Online Registration tab, b) the Register Participant page, and c) the email itself.

After

a) and b) are fixed, because we can override getFieldsToExcludeFromPurification(). However, the email itself is purified in Civi\WorkflowMessage\GenericWorkflowMessage::getUserEnteredHTML(), which has no such bypass.

Comments

Given that this was the very field that let to getPurifiedDefaults() in the first place, I'm not sure we should be bypassing purification.

In fact, it seems like there's a potential security issue here if purification happens before the tokens are rendered.

[civibot]

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