I built a GUI with a treeview based on GTK+3. The tree view does currently not show the expander of the treeview. However, I can see that there is some space reserved for the expander as the indentation of the rows is larger if there is one element with a 'subcategory'.
In addition, I figured out, that the expander is shown if I use another GTK style. Therefore, I tried to change to color of the expander, but it has no effect:
*.view { background-color: ... }changes the background color of the 'buttons' in the tree view. However, the expander is still not visible.treeview.view.expander { color: ...}does not have any effect at all.
Now, my assumption is that the expander is hidden or has some transparency, but I could not find any option to change it.
Do you have any documentation links that explains exactly which CSS option does have an influence on the treeview or its expander or a hint what could be wrong in the CSS file?
Thanks!
