Salut,
Apparemment ce paramètre est personnalisable dans les fichiers de style css du thème que tu utilises.
Ce fichier serait
/usr/share/themes/YOUR_THEME_NAME/gtk-3.0/gnome-applications.css
La propriété CSS à modifier serait
.nautilus-desktop.nautilus-canvas-item
Je parle au conditionnel car je n'ai pas testé moi même la solution.
Source
You have to change the file: gnome-applications.css, located probably in /usr/share/themes/YOUR_THEME_NAME/gtk-3.0
The CSS class responding to desktop icon text is .nautilus-desktop.nautilus-canvas-item.
When you change the color, you have to do more than Alt+F2 and r, it's necessary to kill the Nautilus desktop instance. Simply run killall nautilus, and then open some windowed Nautilus instance -- it should launch the desktop.