How to edit 'non-GTK3' app themes?

Hi, I have been having fun modding a theme just to make it more consistent. So I changed the shadows for apps like nautilus, terminal etc. (basically the ones with the thicker titlebar.) and I can do this quite easily. But the apps with the thinner titlebar, LibreOffice for example - none of the changes in the gtk.css seem to apply to those windows.

Could someone please point me to which files do apply to them? Or which selectors apply to them within the GTK3 css file? because i have folders for metacity, gtk 2.0 etc etc. and I don’t know where to look… and the gtk inspector tool won’t allow me to select the title bar/window either.


I’ve tweak my own theme, i’ve applied my own colors in all the folders on this own theme (in fact a completely based on a Matcha one):
/gtk2.0 +gtk3.0 +gtk4.0

I don’t know what .css is precisely concerned by LO but LO looks as my own now

Thanks for the reply, it’s bizarre to me…

The property I guess I’m interested in at the moment is:

“decoration” and more specifically “.tiled decoration”

I can add/change the box shadows and on nautilus, terminal etc. the shadows of the window will conform to those changes… But not for any application with a thin title bar, so gimp, LO, Inkscape, rhythmbox etc.

I did manage to manipulate elements within rhythmbox with the gtk.css in gtk3 folder… so it must obviously be a gtk3 app… but I have zero clue where it’s pulling the data from for it’s title bar.

I tried deleting various files to see if I could figure it out but no luck…

I have seen other themes add shadows to those apps with thinner title bars when tiled… the Matcha one for example - but I’m struggling with searching online because I don’t really know what my question is lol.

Thanks again though!

I reread you message and saw that you used the Inspector, but maybe the below will help.

I’m on xfce, but assume this will work with the gnome desktop too. But to be honest, I’m not sure how the csd stuff impacts this yet.

Here’s a few links I have in my documentation:

With the Inspector, make sure the Objects label (or is it a button) is selected in the header. The first button’s tooltip is, “Select an Object”. This allows you to select the component in libreoffice that you are interested in, and will position the object inspector.

Then the second button on the top has a tooltip that says, "Show all Objects. After you click that button, in the drop-down, select “CSS nodes”.

When you click the “CSS” label (or is it a button), you can add the CSS right there to try it.

Just a side note: firefox has it’s own inspector in the Web Developers Tools (web page) and the Browser Toolbox (firefox UI). And if you want to use gtk.css, the preference ‘widget.non-native-theme.enabled’ needs to be false, otherwise you need to use userChrome.css.

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Hi thank you,

I will be sure to check out the links. I think I know now why the inspector wasn’t picking up the titlebars of apps like libreoffice, rhythmbox etc. after some fiddling around it seems gnome-shell.css is responsible for the styling these types of windows…

So now I just have to figure out which property is responsible.

Thanks for the links and your input.

Yeah it had nothing to do with the gnome-css… lol was getting in a muddle.

I’d just like to add a shadow to my existing theme when the window is tiled with focus, much like the matcha theme

But I haven’t been able to find the right selector :man_shrugging: