MacOS Ventura and Intel Macs do not work properly with extended displays

I have a late 2019 intel iMac connected with an external display. Everything was working fine until I updated to macOS 13.01 Ventura. With Monterrey, when I set the built-in display as the Main display and the other as an extended display all desktops I created were independent.

For example, I could create 3 desktops on the extended display and 4 on the built-in display and I could go to one or another and browse them independently. Not anymore with Ventura! Now, even with the same set, you can't create independent desktops and if you try to move them, they move all together. If Apple doesn't solve this I will have to downgrade it to Monterrey.

I also have an M1 MacBook pro and connected it to an extended display and it worked fine as supposed, so the problem is only with the intel Mac.

Many thanks for any help,

Marcus