Hi,
if your gtk theme and icon sets of choice are available as snap, then you can apply them to all your snap app’s at once.
Example here is with Adapta gtk I use a lot. And papirus icons.
This ↓ is the first snap package for regular « cyan » adapta gtk theme, which includes also papirus icons.
This ↓ second one is only gtk theme but with all color variants !
Then you have to connect these themes and icons to your snap app’s :
for i in $(snap connections | grep gtk-common-themes:gtk-3-themes | awk '{print $2}'); do sudo snap connect $i adapta-theme-colorpack:gtk-3-themes; done
for i in $(snap connections | grep gtk-common-themes:gtk-2-themes | awk '{print $2}'); do sudo snap connect $i adapta-theme-colorpack:gtk-2-themes; done
for i in $(snap connections | grep icon-themes | awk '{print $2}'); do sudo snap connect $i adapta-gtk-snap:icon-themes; done
If you want to apply theme and icon on a per snap basis :
sudo snap connect chromium:gtk-3-themes adapta-gtk-snap:gtk-3-themes
sudo snap connect chromium:icon-themes adapta-gtk-snap:icon-themes
here ↑ for Chromium with initial adapta “cyan” + papirus icons.
Big thanks to https://forum.snapcraft.io/t/adapta-gtk-theme-colorpack/17891/3?u=coeur-noir and of course @bashfulrobot and @fossfreedom
gimp | chromium
audacity ( beta )