MATE is now using GTK+ 3, according to the release note of MATE 1.18, which is likely the reason why the appearance of MATE desktop has changed regardless of the theme.
- The entire MATE Desktop suite of applications and components is now GTK3+ only!
- Requires GTK+ >= 3.14.
- All GTK2+ code has been dropped [...]
Direct answers
This difference in colour seems related to the Mate version and not to the desktop theme.
The recent version of MATE uses GTK+ 3, which means the desktop theme is now using GTK+ 3 theme and not GTK+ 2 anymore. There is no changes to the theme's background colour itself #accd8a
for Menta. So the colour gradient is one of the differences between GTK+ 2 and GTK+ 3 themes of the particular theme.
I cannot find any options related to the backgrounds of the elements I have indicated above (selected workspace, selected window, selected menu item).
There is no such option by default, regardless of desktop environment. Those detailed configurations are specified in the theme files.
So is there such an option that allows to change the style...
No, or at least I haven't heard any to this answered date.
...or is the new style hard-coded in Mate?
No, the theme is not hard-coded in MATE. The GTK+ 3 theme files can be found in /usr/share/themes/THEME/gtk-3.0
directory of THEME. In newer version of the theme, configuration for MATE desktop components is specified in ../mate-applications.css
file.
Extended answer
When looking into mate-applications.css
file, the relevant parts can be found by using gradient
as keyword. Open the file in a text editor and find using the keyword.
For example, workspace switcher part in Menta theme:
/* selected WnckPager */
PanelApplet.wnck-applet .wnck-pager:selected {
background-image: linear-gradient(to bottom,
@theme_selected_bg_color,
shade (@theme_selected_bg_color, 0.36));
}
The part can be just modified to without the gradient. To begin with, remove linear-gradient(,,)
part and leave only the shade()
and replace background-image
with background-color
(more details in GTK+ CSS: GTK+ 3 Reference Manual). Then, it will look like this:
/* selected WnckPager */
PanelApplet.wnck-applet .wnck-pager:selected {
background-color: shade (@theme_selected_bg_color, 0.36);
}
To see the changes, open Appearance settings in MATE, select any other theme, then select again the last used theme i.e. Menta. No need to log out or restart, just need to reselect the theme. Do similarly for other desktop components i.e. panel menu bar, panel applet, etc.
To prevent loss of modified theme, user should create a copy of existing theme with new name i.e. Menta-custom
and put in /usr/share/themes
. This will make the theme independent and persists between system upgrades.
Disclaimer: I do not use MATE desktop, and I had no time to setup MATE 1.18 for testing; however, theme customization is similarly applicable to other GTK+ environment such as Xfce.
TL;DR The only way to customize the theme to meet user preference, such as removing the colour gradient, is to manually configure the files provided by the theme.
/usr/share/themes/THEME/gtk-3.0
and notgtk-2.0
.gtk-2.0
folder for my theme and restarted the system, but nothing has changed: I still have backgrounds with a gradient instead of a solid colour. Do you think this may be a regression bug?gtk-3.0
differ fromgtk-2.0
in terms of colour shade or even the colour itself. What is the name of theme used by both MATE 1.16 and 1.18?BlueMenta
but the behaviour has changed consistently for other themes, e.g.Menta
.