Icons in top panel of Material Shell are too big

Hello, since I have installed Manjaro on my new Dell XPS 15 7590 (which has a big OLED screen and much higher resolution than my previous laptop), I have noticed that the icons in the top panel of Material Shell are bigger, as if they needed to be zoomed… but they are zoomed too much.

From this screenshot

you can see that the “+” icon and the icon on the right of available layouts are too big. I suspect this is too to incorrect resizing due to screen resolution (3840 x 2160 on my monitor). I have opened a bug on Material Shell’s github page, but I’m posting my issue here as well, in case someone had any idea about how to fix it. It’s not a big problem, it’s merely aesthetic, but it’s annoying.