Arduino 1.8.9 high dpi issue on Linux

[jpeterse]

Updated to 1.8.9 and menu's are not scaled with the Interface scaling setting.
The text in the editor is scaling, but not the menus.
Setting the GDL_SCALE environment variable doesn't work either.

Here's a screenshot comparing the menus from kwrite with arduino editor.

[per1234]

Possibly related:

• very small IDE at screen resulution 3860x2160 #5814
• High DPI unusable on Linux #6472

[stapelberg]

As a shot into the dark: check your gtk-font-name value. I had gtk-font-name "Bitstream Vera Sans 8" in my ~/.gtkrc-2.0. Changing font size from 8 to 12 worked for me.

[jpeterse]

mine is currently:
gtk-font-name="Noto Sans Regular 10"
It looks like the menu's are driven by the font setting in the ~/.gtkrc-2.0 file .
The menu is not changing when the interface scaling is set in preferences.

Issue is, that Arduino IDE is the only application that doesn't display correctly on my PC.
So I don't want to change a global setting, to resolve the issue in a single application.

[eminfedar]

Pardus 19.0 GNU/Linux: (with a screen has 96 dpi), everything is huge except the editor.

[s-light]

same problem - menu font size does not scale..
as discussed here i also tried -Dsun.java2d.uiScale=4 and -Dglass.gtk.uiScale=400% but this did not solve it for me.

the workaround by @stapelberg with setting the font-size in ~/.gtkrc-2.0 did work :-) 👍

so i researched a bit and to only set this for arduino i did the following:

• create a new file arduino.gtkrc-2.0.conf in my arduino folder
• copied & modified the content form the orig .gtkrc-2.0 file to this:

# This only overwrites the Font Settings for Menus to get readable.. :-)
include "/home/stefan/.gtkrc-2.0"
gtk-font-name="Noto Sans Regular 22"

now you can call your arduino ide with something like this:
GTK2_RC_FILES=./arduino.gtkrc-2.0.conf arduino-1.8.10/arduino
(if you are in the directory with the new special gtkrc file)

full path for me is:
GTK2_RC_FILES=/home/stefan/mydata/tools/arduino/arduino.gtkrc-2.0.conf /home/stefan/mydata/tools/arduino/arduino-1.8.10/arduino
and i just used this in my application launcher entry as the command.

[BackMountainDevil]

~/.gtkrc-2.0 not work for Arch KDE + arduino 1.8.5