How to install:
```sudo snap install adw-gtk3-theme
```
How to connect theme:
```for i in $(snap connections | grep gtk-common-themes:gtk-3-themes | awk '{print $2}'); do sudo snap connect $i adw-gtk3-theme:gtk-3-themes; done
```
Snaps are applications packaged with all their dependencies to run on all popular Linux distributions from a single build. They update automatically and roll back gracefully.
Snaps are discoverable and installable from the Snap Store, an app store with an audience of millions.
Enable snapd
On Debian 9 (Stretch) and newer, snap can be installed directly from the command line: