Hello,
I’m trying to install Manjaro GNOME from the live USB on an Acer laptop and I have a strange graphics problem.
When I boot the live session (both with open source and proprietary drivers), the desktop loads correctly (wallpaper + top bar), but when I open any application the windows appear behind the wallpaper. I can see the applications in the dock/taskbar and when I switch with Alt+Tab I can briefly see them under the background image.
I already tried:
Boot with open source drivers
Boot with proprietary drivers
Adding nomodeset to the kernel line
Restarting GNOME Shell with Alt+F2 → r
The problem persists. The system is usable enough to open the installer, but the windows stay under the wallpaper.
Laptop: Acer (I can provide more hardware details if needed)
Any idea how to fix this in the live session or is it safe to just install and hope it works after the first reboot?
Thanks in advance.
Welcome to the forum! 
With the disclaimer that I’m not a GNOME user and that I don’t have any Nvidia hardware, I don’t think your problem would be caused by the graphics drivers.
Note: I have added the nvidia tag to the topic because you mention proprietary drivers, and both AMD’s and Intel’s drivers are Free & Open Source, leaving Nvidia as the only real provider of proprietary drivers — there is a proprietary AMD driver as well, but most people won’t have a need for that.
That said, the behavior you’re reporting is certainly peculiar, and most likely specific to the live ISO only — possibly some bug crept into the mastering process — which in theory should make it safe to install.
Still, I think this warrants investigation, so could you tell us what hardware is in your system — if possible, post an inxi output as per the links below… 
- How to post screenshots and links
- How to find error logs
- How to find system information
- How to post text information as preformatted text
- How to reach a minimal system
- How to use the terminal/
tty - How to use public Pastebin services
Also, what ISO did you use — as in, “where did you get it from, and what was its name”?
For Manjaro and I chose Gnome, the latest version
Some has marked the post immediately before this as the solution to this topic – somewhat non-sensical.
I have removed the marked solution posrt in lieu of there being an actual solution provided, or the OP marking a post that actually provides a solution.
If it was you (the OP) who marked that post as the solution, I’m afraid you will need to perform some research into how a Discourse based forum actually works.
Even the installer is hidden?
What does inxi -Gxx / echo $XDG_SESSION_TYPE / inxi -Fazy show