there is no direct or simply way to configure what we need in question.
But it can be done by editing the User Shell theme that is in use.
if you are using default theme in 18.04, below is the way to achieve.
first take back up of /usr/share/gnome-shell/theme/ubuntu.css
file.
now open the file with you favorite text editor, mine is gedit, so
sudo -H gedit /usr/share/gnome-shell/theme/ubuntu.css
go to line number 1205 and find the below content.
.dash-label {
border-radius: 7px;
padding: 4px 12px;
color: #eeeeec;
background-color: rgba(46, 52, 54, 0.7);
text-align: center;
-x-offset: 8px; }
Change it to
.dash-label {
border-radius: 7px;
padding: 4px 12px;
color: #eeeeec;
background-color: none;
font-size: 0pt;
text-align: center;
-x-offset: 8px; }
save the file & close. Reboot to see the change.
if you use different User-Shell themes, you may find same content and editing it as above.
In a fresh install of Ubuntu 20.04,
the default shell theme.. and lock screen both are configured to use the css file
Yaru/gnome-shell.css
which is inside the /usr/share/gnome-shell/theme/Yaru/gnome-shell-theme.gresource
this is configured in the file /usr/share/gnome-shell/modes/ubuntu.json
{
"parentMode": "user",
"stylesheetName": "Yaru/gnome-shell.css",
"themeResourceName": "theme/Yaru/gnome-shell-theme.gresource",
"debugFlags": ["backtrace-crashes-all"],
"enabledExtensions": ["ubuntu-dock@ubuntu.com", "ubuntu-appindicators@ubuntu.com", "desktop-icons@csoriano"]
}
So, you can pointout what ever .gresource
file you want to use and the corresponding gnome-shell.css
for example, If I want Yaru-dark theme, I can simply point out like this by editing the file /usr/share/gnome-shell/modes/ubuntu.json
Take Backup of the file /usr/share/gnome-shell/modes/ubuntu.json
before editing
{
"parentMode": "user",
"stylesheetName": "Yaru-dark/gnome-shell.css",
"themeResourceName": "theme/Yaru/gnome-shell-theme.gresource",
"debugFlags": ["backtrace-crashes-all"],
"enabledExtensions": ["ubuntu-dock@ubuntu.com", "ubuntu-appindicators@ubuntu.com", "desktop-icons@csoriano"]
}
Please note that Default shell theme and lock screen uses same file.. so If you want Yaru shell theme for the desktop session.. you need to install it as a local theme which is another topic.
I have not tried with full path of the .gresource
file.. in the line
"themeResourceName": "theme/Yaru/gnome-shell-theme.gresource",
this means.. theme/Yaru/gnome-shell-theme.gresource
is a relative path of the base /usr/share/gnome-shell
Best Answer
you are using Yaru-dark as shell theme..
so edit the file
/usr/share/themes/Yaru-dark/gnome-shell/gnome-shell.css
around line number 1493 add the line as below..
My final edits are