R2022b Simulink is unusable on dark themed KDE

Problem: Simulink is unusable - white text on white/grey background, which makes the text unreadable, the tool strip (top of the GUI) is normal), but the bottom 3/4 of the GUI (the schematic editor in the middle, property inspector on the right, model browser on the left), is completely unusable.

Matlab is OK (the classic light theme), and Preference/Colors is NOT set to follow system (the OS's theme is plasma breeze dark).

If no definite solution to fix it can be provided, can someone point out the GUI technology behind the simulink window so I can try to fix it myself? It doesn't seem to be the same with the one used by matlab (which is some kind of java GUI I guess), is it built on web viewer (it feels like one)? Gtk web view or Qt web view?

Thanks.

Operating System: Red Hat Enterprise Linux 8.6

KDE Plasma Version: 5.23.3

KDE Frameworks Version: 5.88.0

Qt Version: 5.15.2

Graphics Platform: X11

Answer 1

[Franklin Ronald]

Hi.

I'm using environment variables to set a light theme to MATLAB only.

XDG_CURRENT_DESKTOP=GNOME
GTK_THEME=Adwaita:light

And Simulink is light but usable.

[Devin]

Hi all,

This fix does work great but if you launch MATLAB through the GUI like I do you can apply this fix permanetly by editing MATLAB's .desktop file.

Find MATLAB’s .desktop file (Usually in /usr/share/applications/matlab.desktop or ~/.local/share/applications/matlab.desktop).

Edit it using a text editor:

nano ~/.local/share/applications/matlab.desktop

Find the line starting with Exec= and modify it like this:

Exec=env XDG_CURRENT_DESKTOP=GNOME GTK_THEME=Adwaita:light matlab -desktop

depending on how your .desktop is set up it may be the directory to the MATLAB launcher and in that case, put

env XDG_CURRENT_DESKTOP=GNOME GTK_THEME=Adwaita:light

before the dierctory like so.

Exec=env XDG_CURRENT_DESKTOP=GNOME GTK_THEME=Adwaita:light /usr/local/MATLAB/R2024b/bin/matlab -desktop

Save and exit, then refresh the desktop database:

update-desktop-database ~/.local/share/applications

Now, MATLAB should always launch with these environment variables, even from the GUI.

Answer 2

[Navya Singam]

Hi,

The team is aware of the issue and it may be fixed in the future releases.

The only way to solve the issue is to turn off the dark theme on system and then reinstalling MATLAB.

[Jan Mertes]

Hello,

is there a possibility to solve the problem yet?

I have exactly the same problem.

System: OpenSUSE Tumbleweed; Kernel: 6.6.6.1; Dekstop: KDE Plasma 5.27.10 with a Dark Theme (Breeze) on X11.

Kind regards