Zammad: Cannot use ticket templates since 2.4 anymore

Infos:

• Used Zammad version: 2.4
• Installation method (source, package, ..): deb package
• Operating system: Ubuntu 16.04
• Database + version: MySQL 5.7
• Elasticsearch version: 5.6.8
• Browser + version: Firefox & Chrome latest

Expected behavior:

• I create a new ticket
• I select a template and hit apply
• The template is selected and used for the ticket

Actual behavior:

• The template is not used
• nothing happens (no log entry on server or client)

Steps to reproduce the behavior:

• Create a new template

• Select this template for a new ticket

• It is possible to create new templates (log looks normal)

• It is also possible to delete templates

Yes I'm sure this is a bug and no feature request or a general question.