Thanks for the fast answer... but...
The 5.0.5 version solved the "saving problem"? So that's exaclty when i've found that issue, because before i didn't had it.
When i press "save" to save a page with a even a minor change, the system takes some time and than gives back this message: "Cannot read properties of undefined (reading 'message') "
I must say that i found no issues at all in all my sites until the moment i've upgraded to 5.0.5. The upgrade woked perfectly in all sites, but now i have this bug.
Thanks