Customized email templates
Before Nextcloud 12 email templates could be changed using the Template editor app. This app worked as following:
1. The code could be changed in the admin interface and any script added would execute when the email is sent.
2. When the PHP syntax was invalid (missing a semicolon or closing bracket) the email would not be sent at all, without any trace in Nextcloud itself, because the syntax error would just stop Nextcloud.
3. When an email template was updated with a server update, the changes were copied to custom templates. (e.g. when we added/removed information/variables to/from the share email)
Custom Email Template
With Nextcloud 12 we introduced a new way of modifying emails. The existing Template editor app is not suited for this anymore and is discontinued. Additionally we improved the look of the default emails when theming is enabled to cover more cases.
The new way of modifying emails works by creating a simple app which contains your customization. In this app you creat