I haven't had time to run Ubuntu Budgie to test this. The icon is depended on the theme and things might have changed there in Budgie.
So can you run the following command replacing MYTHEME with the theme you are using:
ls -lR /usr/share/icons/MYTHEME/ > icons.txt
Attach icons.txt here and state what theme you are using. This might help in figuring out what needs to change.
I haven't had time to run Ubuntu Budgie to test this. The icon is depended on the theme and things might have changed there in Budgie.
So can you run the following command replacing MYTHEME with the theme you are using:
ls -lR /usr/share/ icons/MYTHEME/ > icons.txt
Attach icons.txt here and state what theme you are using. This might help in figuring out what needs to change.