On a couple of website I have discovered that the module assignments can become effectively randomised when Gzip is enabled in global settings. This appear to be a recent phenomena.

Any ideas, other than not using gzip?

That's what I thought. I then disabled all the caching I could find, including that in Global Settings. Deleted the existing caches and expired cache. Still had a problem. Switch Gzip on and off clearly switched the assignments around.

So far two of my websites have been effected. It is a recent problem so I don't know if it's related to recents Joomla updates. The sites are currently on V 3.10.4

Same problem here: imaginefilm.be/fr/films/item/1423-great-freedom

This page should not show the top picture, this module sonly allowed on the films menu but not in child pages and excluded in Flexicontent Content Item

It was working fine for 2 years but is now broken. It works fine when cache is disabled.

Any ideas?

To be fair I'm not keen to experiment on what is a very busy website. The effect turns the whole website into a complete mess. Ideally I would need to set up a development site for this.

The problem is also there when using the core module manager.

@jean

did you uninstall the Module Manager or just switch to the core?

I tried an uninstall but the Red Cross at the right was still there