First install the adw-gtk3 package.
| Fedora | dnf install adw-gtk3-theme |
| Arch | pacman -S adw-gtk-theme |
| Debian | 3rd party repo |
Then open your terminal and make the following changes to the environment file.
sudo nano /etc/environment
QT_QPA_PLATFORM=xcb
QT_STYLE_OVERRIDE=adw-gtk3-theme
Optional
GSK_RENDERER=ngl
FREETYPE_PROPERTIES=“cff:no-stem-darkening=0 autofitter:no-stem-darkening=0”