In configuration of the form dialog there are two fields (HTML and PlainText E-Mail). Both are configured as i18n. But there will be not updated if i changed my language and the email will not send with a i18n text. There is still one language for this. If i add i18n=true to the dialogRadioSwitch the german language will be shown in german but in the second language english there is no textarea anymore. This should be an error. On the other hand it should be also possible to translate the Textfields over the ContentTranslation Tool. More information in SUPPORT-2047