hello, it seems to me that we can edit "TAB" and send a grub or syslinux a "vga = 893" (see the VESA_BIOS_Extensions correspondence table) for the live / initrd.img https://en.wikipedia.org / wiki / VESA_BIOS_Extensions
and that's the same problem with grub boot and debian-installer.

vga=test-kali.png (126,429 bytes)   

vga=test-kali.png (126,429 bytes)   

I guess you have the same issue in non-live mode, i.e. if you install the system. This is really a problem that should be handled by the various desktops and not by us Kali.

It seems that GNOME has automatic support for this:
https://wiki.gnome.org/HowDoI/HiDpi

But Xfce doesn't seem to have anything automatic and it seems to be painful to configure:
https://forum.manjaro.org/t/wiki-xfce-settings-for-high-resolution-monitors/51534

So yeah, downgrading the resolution might be the easier approach.

Still I want to know. On a fresh live boot, what do you get as output for "xrandr" ?

Does "xrandr --dpi 196" gives a good result?

Does "xrandr --output XXX --scale 0.5x0.5" gives a good result?
(try on a fresh boot, without having called xrandr --dpi 192 first)

I have read about "slick-greeter" supporting HiDPI. Maybe we should try to use it on a HiDPI screen and see if the sessions started through it behave better... I don't have any HiDPI screen to test anything though.

Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 16384 x 16384
eDP-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 309mm x 174mm
3840x2160 60.00*+ 59.98 59.97 48.00
3200x1800 59.96 59.94
2880x1620 59.96 59.97
2560x1600 59.99 59.97
2560x1440 59.99 59.99 59.96 59.95
2048x1536 60.00
1920x1440 60.00
1856x1392 60.01
1792x1344 60.01
2048x1152 59.99 59.98 59.90 59.91
1920x1200 59.88 59.95
1920x1080 60.01 59.97 59.96 59.93
1600x1200 60.00
1680x1050 59.95 59.88
1600x1024 60.17
1400x1050 59.98
1600x900 59.99 59.94 59.95 59.82
1280x1024 60.02
1440x900 59.89
1400x900 59.96 59.88
1280x960 60.00
1440x810 60.00 59.97
1368x768 59.88 59.85
1360x768 59.80 59.96
1280x800 59.99 59.97 59.81 59.91
1152x864 60.00
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)

xrandr --dpi 196 does help, and "xrandr --output XXX --scale 0.5x0.5" works as well however things do start to look "fuzzy" across the board and the cursors get oversized.

Arch has a good guide at https://wiki.archlinux.org/index.php/HiDPI and for XFCE 4.14 does have better HIDPI support however when we change the scaling to 2x it does not impact all apps, most notably the terminal. Running "xrandr --dpi 196" combined with the XFCE change makes things usable (not perfect, but acceptable).

It seems like we could use an automated way of setting the xrandr dpi when on a hidpi display?

We have kali-hidpi as workaround now, closing this ticket.