I installed AL with i3 as wm. I am on a high dpi display, so first of all I changed the dpi in the .Xresources file. So the i3 bar, rofi etc are decently scaled. But other apps such as firefox or lightdm settings are too small. Also, I use urxvt as default terminal (which I also control via .Xresources) which shows too small scaling after rebooting. Only when I run manually ‘xrdb ~/.Xresources’ and then pull up a new terminal, terminal font sizes are set correct…
I’m on a 4k screen myself. Unfortunately there is nothing you can do about LightDM or any Login Manager for that matter.
As far as Firefox is concerned.
In a new tab open about:config
Search for layout.css.devPixelsPerPx and change it to the scale you want. I use 1.25
Put this in your .xinitrc, if you have something similar we may have to dig a bit further.
if [ -f $sysresources ]; then
xrdb -merge $sysresources
if [ -f $sysmodmap ]; then
if [ -f "$userresources" ]; then
xrdb -merge "$userresources"
if [ -f "$usermodmap" ]; then
This will only work if you’re using xinit as a login manager. It would also rely on all the variables used being defined $sysresources, $userresources etc. (they’re certainly not in the posted snippet!)
Try using the actual path to your file and put it in ~/.xprofile instead, it’s loaded by login managers like lightdm.