Gnome 3 (Gnome Shell) JavaScript/CSS engine

Question

I am wondering, which type and version of JavaScript/CSS engines is Gnome 3 aka Gnome Shell using?

Is there any information about current version, etc?

Answer 1

For JavaScript the engine GJS (based on SpiderMonkey). For theming, it is used a sort of superset of CSS2. You might be interested in reading the documentation of GtkCssProvider and the migration information.

On the other hand, there are some CSS3-like operations available, such as radial and linear gradients. You might want to take a look the article Styling GTK+ with CSS to get some ideas. The article was written by the developer who wrote GtkCssProvider.