Well, something weird happened to me with this update. Installation this morning was successful, dbus-broker as default, kernel 6.6.10-1, restart, no errors, I can login, network ok, internet ok, it seemed another boring update. 
I noticed the problems while browsing internet (Brave Browser). Strange artifacts appear on screen as you can see in these screenshots:
First the screen was ok and as I move the mouse, suddenly this artifacts appear.
Reading newspapers with Firefox sometimes some images appear only half bottom, other small images seem missing and reappear while scrolling… yesterday (before the update) none of this happened. And Brave Browser wasn’t updated.
This is info about my AMD graphic card:
Graphics:
Device-1: AMD Caicos PRO [Radeon HD 7450] driver: radeon v: kernel
Display: x11 server: X.Org v: 21.1.10 driver: X: loaded: radeon
unloaded: modesetting dri: r600 gpu: radeon resolution: 1920x1080~60Hz
API: EGL v: 1.5 drivers: kms_swrast,r600,swrast
platforms: gbm,x11,surfaceless,device
API: OpenGL v: 4.5 vendor: mesa v: 23.1.9-manjaro1.1 renderer: AMD CAICOS
(DRM 2.50.0 / 6.6.10-1-MANJARO LLVM 16.0.6)
API: Vulkan Message: No Vulkan data available.
AMD driver seems to be loaded and OK as usual:
> 0000:01:00.0 (0300:1002:677b) Display controller ATI Technologies Inc:
--------------------------------------------------------------------------------
NAME VERSION FREEDRIVER TYPE
--------------------------------------------------------------------------------
video-linux 2018.05.04 true PCI
video-modesetting 2020.01.13 true PCI
video-vesa 2017.03.12 true PCI
> 0000:04:00.0 (0200:10ec:8168) Network controller Realtek Semiconductor Co., Ltd.:
--------------------------------------------------------------------------------
NAME VERSION FREEDRIVER TYPE
--------------------------------------------------------------------------------
network-r8168 2023.09.12 true PCI
So I tried deleting cookies and cache in both browsers, restarting with Kernel 5.15.146-1 → the same problems. Search journalctl, dmesg, reboot without “quiet” in Grub and found no errors.
Since I made a timeshift snapshot just before the update, I restored it and oooopsss → problem solved. No artifacts browsing the forum, no half images in Firefox…
Next step: upgrade kernel to 6.6.10-1. Still no artifacts, so this seems something not kernel-related but update-related.
So I’ll keep my current configuration, wait sometime before upgrading again and see if anyone has the same issues.