Redmine

Hi,

I'm running Redmine from Debian jessie (version 2.5.2 devel - "a snapshot of the development branch that would become redmine 3.0 before it was officially released") with Apache 2.4 + Passenger + Mysql.

My problem ist that the preview of wiki pages/ tickets etc. doesn't work. After clicking the preview button nothing happens.

My webbrowser tells me:

Failed to load resource: the server responded with a status of 404 (Not Found)

The production log:

Started POST "/issues/preview/new/test" for 10.0.1.1 at 2016-01-06 22:08:26 +0000
Processing by PreviewsController#issue as URL_ENCODED_FORM
  Parameters: {"utf8"=>"<E2><9C><93>", "authenticity_token"=>"X4/hyNwlHewlZa0EhqMVYtwcm/UE+vc2Ov6F7ETClDc=", "issue"=>{"tracker_id"=>"1", "subject"=>"test", "description"=>"test", "status_id"=>"1", "priority_id"=>"2", "assigned_to_id"=>"", "start_date"=>"2016-01-06", "due_date"=>"", "estimated_hours"=>"", "done_ratio"=>"0"}, "project_id"=>"test"}
  Current user: test (id=8)
Missing template, responding with 404

As it's a newly created installation with no plugins I have no idea what causes this. How can I further debug it?