adw-gtk3

The default theme from libadwaita ported to GTK-3

Note that this is not a 100% accurate port.

adw-gtk3
Installation from tarball

Go to the releases section and download the latest tar.xz file.

For a local install: Unpack the file to ~/.local/share/themes/
For a global install: Unpack the file to /usr/share/themes/

Installation from source (Recommended)

This will install the latest version from the main branch.

ArchLinux users can skip the below steps and install it from AUR: https://aur.archlinux.org/packages/adw-gtk3-git/ (Maintained by 3rd party)
Requirements

GTK 3.24.13+

Debian/Ubuntu/Mint/PopOS - apt install ninja-build git meson sassc
Fedora - dnf install ninja-build git meson sassc
Arch/Manjaro - pacman -S ninja git meson sassc
OpenSuse - zypper in ninja git meson sassc

Other distros may have named the above packages differently.

When the above requirements are installed, simply run these commands:

git clone https://github.com/lassekongo83/adw-gtk3.git
cd adw-gtk3
meson build
sudo ninja -C build install

The theme(s) will be installed in: /usr/share/themes/
Local installation

Install the theme(s) locally if you for some reason can't run as a sudo user. Fedora Silverblue users can use this install option.

git clone https://github.com/lassekongo83/adw-gtk3.git
cd adw-gtk3
meson -Dprefix="${HOME}/.local" build
ninja -C build install

Updating the theme

Navigate to the adw-gtk3 folder that was originally cloned. (If you removed it, do the steps above instead). Then run:

For a global install:

git pull
sudo ninja -C build install

For a local install:

git pull
ninja -C build install

Flatpak

If you want to use this theme in flatpak applications, run these commands:

Light theme: flatpak install org.gtk.Gtk3theme.adw-gtk3
Dark theme: flatpak install org.gtk.Gtk3theme.adw-gtk3-dark

The above commands assumes that you have the flathub respository active. If not: flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

Thanks to @dusansimic for the help.
How to change themes

Use gnome-tweaks to change your GTK3 themes.

You can also change your GTK3 themes using the terminal:

# Change the theme to adw-gtk3
gsettings set org.gnome.desktop.interface gtk-theme adw-gtk3

# Reverting the change to the default GNOME theme
gsettings set org.gnome.desktop.interface gtk-theme Adwaita

Dark theme issues

For GNOME 42+ using gnome-tweaks won't be enough.

Open GNOME settings > go to the Appearance section > select Dark.
Open gnome-tweaks and set the theme to adw-gtk3-dark.
If you use flatpak applications, install: org.gtk.Gtk3theme.adw-gtk3-dark.

How to remove the theme(s)

To be safe from any crashes or weirdness, change the theme to another one before running the command below.

For a global install: sudo rm -r /usr/share/themes/adw-gtk3*

For a local install: rm -r ~/.local/share/themes/adw-gtk3*

Flatpak: flatpak uninstall org.gtk.Gtk3theme.adw-gtk3 && flatpak uninstall org.gtk.Gtk3theme.adw-gtk3-dark

I ( Kushagra Karira ) is not the maintainer of this project, but authorized to post here