i made a tool called castly to do this, instead of this janky gnome extension fork https://github.com/rgbmew/castly
A small collection of GNOME-related things I made for this Reddit post.
This folder contains a small fork of Custom Accent Colors by demiskp to add titlebar tint. Just like with the original extension, you need to relog for it to take full effect.
It's also worth mentioning that the way I added the titlebar tint, some GTK3 windows don't play well with it, and just use the default white/black. This happens because I set transparency for the titlebar color, so it works in both dark and light mode. If anybody knows a way to change colors based on dark/light without using transparency to overlay it on the original titlebar color, please send a PR! Although they SHOULD work with all normal titlebars for legacy apps, and all libadwaita titlebars.
This is another change that I made to Custom Accent Colors. You can load other custom CSS in addition to the custom accent color.
The original Accent Colors extension would just overwrite any CSS that was in ~/.config/gtk-4.0/ and ~/.config/gtk-3.0/. The edit I made is that it will still overwrite those files, but ALSO look for more CSS in ~/.config/gtk-4.0/more.css, if you have more custom CSS you want to load (like the Unite extension, or small edits to libadwaita).
The file in there right now is a small example of what you can do with it. I changed the roundness of tabs, the sharpness of window corners, and added an example for how to add Unite support.
A compact version of adw-gtk3! This basically only effects the size of window titlebars. I also added comments in /gtk-3.0/libadwaita.css that say "EDIT HERE!!!!!!!!!!!!!!!!!!!!!!!!1" if you want to change the sharpness of window corners. All other changes can be easily understood by comparing the original adw-gtk3, and adw-gtk3-compact in Meld.
Special thanks to demiskp for making an awesome extension, and lassekongo83 for making an awesome theme!
Blue wallpaper by desktopGeneration
Green wallpaper originally from Cardcaptor Sakura merchandise
Yellow wallpaper by NAT KING (and upscaled using Upscaler)