Some stock icons no longer available in GTK+3 with adwaita-icon-theme-42 and gtk+-3.24.33
adwaita-icon-theme-42.0 has retired all or most of its legacy (non-symbolic) full-color icons. Following this, gtk+-3.24.33 can no longer find some stock icon names from adwaita-icon-theme's symbolic icons.
For example, obtaining a new button with gtk_button_new_from_stock(GTK_STOCK_ABOUT);
or a new image with gtk_image_new_from_stock(GTK_STOCK_ABOUT, [size]);
using adwaita-icon-theme-42.0 will generate the error message Error loading theme icon 'help-about' for stock: Icon 'help-about' not present in theme Adwaita
, and attempting to use GTK_STOCK_QUIT
will generate the error message Error loading theme icon 'application-exit' for stock: Icon 'application-exit' not present in theme Adwaita
, and so on.
I realize that the stock macro names are not intended to be used in new code since gtk+3.10 (in particular, you are supposed now to use gtk_button_new_from_icon_name), but it seems to me that for legacy code gtk+-3 should still be able to generate the necessary stock images from adwaita's symbolic icons by carrying out the relevant name conversions.