For specific GTK3 apps
Edit their .desktop
file (Nautilus' is located at /usr/share/applications/nautilus.desktop
)
And add env XDG_CURRENT_DESKTOP=GNOME
just after each Exec=
line. For example, nautilus.desktop
's Exec=
line(s) (It has two, one for opening a new window) will change from...
Exec=nautilus --new-window %U
[… Some other lines, skipping …]
Exec=nautilus --new-window
to
Exec=env XDG_CURRENT_DESKTOP=GNOME nautilus --new-window %U
[… Some other lines, skipping …]
Exec=env XDG_CURRENT_DESKTOP=GNOME nautilus --new-window
NOTE: If you use Unity, do the same to /usr/share/applications/nautilus-autostart.desktop
and/or /etc/xdg/autostart/nautilus-autostart.desktop
.
(You may have to logout/login.)
For all GTK3 apps
Word of warning: Telling all apps that the DE is GNOME may result in side effects.
Edit: Unity fails to start with this.
Edit ~/.profile
and add a line:
export XDG_CURRENT_DESKTOP=GNOME
then all apps will obey this.
I was able to add border to windows in Ubuntu 18.04 by doing the following:
nano ~/.config/gtk-3.0/gtk.css
Then add the following:
decoration {
border: 3px solid gray;
background: gray;
}
After saving the file, remember refresh gnome using this command:
setsid gnome-shell --replace
I found it works well for Ambiance. I like the border slightly thicker (3px) to make it a little easier to see in laptop running in 1920x1080 resolution.
EDIT:
To customize the active title bar background colors. (use :backdrop for inactive windows)
.titlebar {
background: #0759EB;
}
.titlebar:backdrop {
background: #829EDF;
color:white;
}
Best Answer
Edit the files in the directory:
To avoid clobbering the original them it's better to copy the them to your personal area under a different name, then make the changes. The theme will appear in the theme chooser as the name you copied them to.
Per-user theme ares:
Specifically to this question you can change the color of the title bar by changing: (There are many ways but this is a start to change the border color of the active widget of the Radiance theme from the original default gray to a bright blue).
1 (Border Top)
Change from:
Change to:
2 (Border Right and Left side)
Change from:
Change to:
3 (Border Bottom)
Change to:
You can do the same thing with the ":backdrop" entry to change the color of the inactive window border colors. The #0000ff color code is blue. I made the backdrop #0000ff back to make it easy to tell which of my many open windows is active.
Because of the dark color frames (after changing the very light borders of the Radiance theme) the text color had to be changed from the default black to make it readible. For this use the following in each of the feature blocks:
That takes care of the frame color and text of the modified theme. For the border width:
Edit the block:
UnityDecoration
{Change from:
Change to:
Details of the features can be found at:
https://wiki.ubuntu.com/Unity/Theming
You have to use the unity-tweak-tool to select your custom theme: