PureOS KDE / plasma amber laggy


I’ve just done a fresh install of PureOS plasma amber from https://downloads.pureos.net/amber/live/plasma/ on a Librem 15v4 and I’m noticing that everything is a little laggy.

Menus don’t open very fast, the text as I’m inputting it is a little slow, and mouse clicks are registered a touch slow. Any known issues that might be causing this?

One thought I had: could it be my display setup? I’m driving the internal 4K display in the 15v4 and an external 1920x1080 display with this xrandr command: xrandr --output eDP-1 --primary --auto --scale 0.9999x0.9999 --pos 0x2160 --output HDMI-1 --auto --scale 2x2 --pos 0x0

This, combined with setting the internal monitor scaling to 2x in Plasma’s displays menu, results in a somewhat fuzzy but usable 1920x1080 external display directly on top of a sharp 4K internal display, all while having everything reasonably sized in both monitors. If you try to use just plasma displays, X limits you to one scaling factor for the whole thing, so you can have tiny text on your 4K display or huge stuff on 1920x1080. Wayland doesn’t seem to work well enough in plasma / amber yet (e.g., Firefox Wayland doesn’t work).

The reason I bring it up: I think I’m forcing X to render a very large display space and then use only parts of it, so maybe this could be causing some of my issues? Unplugging the display doesn’t help.

Anyone else using plasma? Does it work fine? Do you also experience generalized lagginess?