No content in event details page

... the issue is also with the Casseiopia template if it is not set as default.
I will set up a test server with fresh JEM and Purity IV installation and check their.
Maybe best is to display the details in an modal window using usescript dialog autocreate. That did work in another context. 
 

I cannot reproduce your issue in Cassiopeia. Could you give me the steps to reproduce it in Joomla 5.4 with Cassiopeia and JEM 4.3.4?

Installing purity iv, setting layout to business,
Creating a copy with layout default and setting that as default style.
Then just create a hidden menu item, jem simplelist and template casseiopia
Then cleared the cash on server on browser.
the page is here: - can not add a link : - (     it is page test-event-details at domain

I have tested the Purity IV template with the default layout, and it’s working, because the default layout works with module positions. It also works if the menu for the JEM module (Teaser) is configured with the Cassiopeia template.

However, the Business layout (in Purity IV) doesn’t work with module positions and only uses its own section system. I don't know how compatible this is or whether Joomla's module management system supports it. I'm sorry but I haven't used that template.

Do you have access to the hidden menu in your browser? Does it work?
If you look at the module page, everything is correct.

Yes I know - the purity iv business layout is "special" and the default layout is more "joomla standard". The idea was to use the business layout for landing page (see pcagev dot de) and for all pages where this layout causes issue to use the purity iv default styles. 
Unfortunately that did not work for the JEM teaser modul  link pointing to the details page. 

Good to read that in you set up the purity iv with default layout works fine. So I assume that something is wrong with my installation or overrides. 
I will set up a test sever with a fresh joomla purity iv and jem installation an come back next week. 

The hidden menu is at pcagev de  and then / test-event-details  and yes it show the list of events (simpellist) but the details page are empty

ps: i am struggling with this md editor (i am familiar with github) - links and code is difficult to insert. 

 

On the right side of Purity Business, the JEM Teaser module is working. See image.