a few months ago i installed Manjaro in a virtual machine on my laptop. everything went semi-ok so i decided i wanted to install it on my laptop fully, then when i did, the ui, cursor and task manager was WAY too small. So i changed global scaling and the other things so that it was bearable. now when i connect my monitor it (somewhat unsurprisingly) makes everything very big so its unusable again.
so how do i change it so that either:
the monitor doesn’t keep the changes i made in global scaling, task manager and cursor settings or
so that my laptop, by default has a normal ui, cursor and task manager.
That’s a weird laptop architecture given that the screen resolution is 3840x2160.
The problem is in the graphics driver; it doesn’t properly handle graphics resolution higher than 1920x1080.
I thought initially that your laptop had an NVIDIA GPU … , because if so, I know that using NVIDIA proprietary graphics driver will fix the resolution issue.
Your current graphics driver is video-linux. So my advice is to try installing video-modesetting graphics driver first: sudo mhwd -i pci video-modesetting, then reboot. If the resolution is still not fixed, then try video-vesa: sudo mhwd -i pci video-vesa and then reboot.
But from my experience, open-source graphics driver currently doesn’t seem able to handle ppi for resolution higher than 1920x1080 well. Scale to 200% or higher may fix the DE look, but some GUI application UI may still suffer.
I have a laptop with screen resolution like yours, 2560x1600, and UI looks small on Manjaro. I switched to a deb or rpm based distro to get the official NVIDIA drivers support and it fixed the whole small UI issue.
OP’s screen resolution is twice of 1920x1080, so I expect GUI widgets will look twice smaller than the normal.