I have xUbuntu 18.04.4 LTS (XFCE 4.12 + 4.15.0-111 Linux kernel) on the Dell Vostro 3360 laptop. When I connected the external display (Samsung SyncMaster T240) via VGA cable - all is good and I got such xrandr output:
xrandr -q *** VGA-1 connected 1920x1200+1366+0 (normal left inverted right x axis y axis) 518mm x 324mm 1920x1200 59.95*+ ***
But when I connected this one via HDMI cable the size of this display isn't detected correcltly (in the XFCE Display window it shows as Samsung 7") and I got such output:
*** xrandr -q HDMI-1 connected 1920x1200+1366+0 (normal left inverted right x axis y axis) 160mm x 90mm 1920x1200 59.95*+ ***
Accordingly, some apps such as Viber or Caliber are displayed with "huge controls".
How I can fix this problem (desirable - not only for this display, but for HDMI-connections at all)?
for now looks like problem is in EDID-information that is sending by external-display via HDMI (and NO,
xrandr --fbmm doesn't works...)