full-upgrade : 20 mins later KWIN crash, flickering destkop!

Want to know guys i’ve made : sudo apt update && sudo apt full-upgrade …
Restarting the VM : i get totally corrupted GUI (flickering and artefacts all over the place) …
Kwin is crashing as well, desktop is black : everithing was fine before updating …
KDE users someone has the same trouble : flickering, desktop vanishing, black screen and icons missing ?
i havent update my video card drivers, i want to understand and troubleshoot if a good soul can help me please dont want to build an another VM (and i have no backup of this one) …
Thx in advance Saltinbank

Latest upgrade contains package version conflict from Debian testing. Core packages of KDE were removed. I suggest you track this topic for more update.