Please help us help you and fill where relevant:
Your LimeSurvey version: 6.5.9.+240521
Own server or LimeSurvey hosting:
Survey theme/template:
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Last week updated to 6.5.9.+240521. After the updated, the toolbar is missing in E-mail templates, but only for surveys created after the update. Surveys created before the update, still have the toolbar.
Even if I create a new survey and say it to be a copy of a survey created before the update, the new survey is missing the toolbar.
I've added two attachments, one of a survey created before the update and one of a survey created after the update.
I hope anyone can help.
 

Set the Participant Setting "Use HTML format for participant emails" to On, fixed the issue.
Not trying to find out how to change the default setting from Off to On