Comment 11 for bug 1721955

My hunch is that this has to do with how the Human themes have theme definitions for GTK2 but not GTK3—other themes like this seem to be having similar problems, now.

The best workaround I’ve found is this one: https://www.opendesktop.org/s/mate/p/1013593/ It took a little bit of fidgeting for me to get this to work correctly, and there are still some bugs, but someone has created workable new versions of the Human themes. Personally, I used the “Human Quarny Clearlooks” theme, by copying its folder (renaming it “Human-Quarny-Clearlooks”) into “~/.themes”, then copying the “metacity-1” folder from “Human Quarny” into “Human-Quarny-Clearlooks”, and updating the index.theme file to rename the theme “Human Quarny Clearlooks” and then specify the sub-themes (except for icon theme, which stays “Humanity”) as “Human-Quarny-Clearlooks” instead of just “Human”). …That was way too complicated, but just copying the theme folders into “~.themes” created four or so different “Human” themes in the “Appearance” theme selector, and I had a feeling that madness lied that way.

Oh, and the most obvious bug I’ve found is that some applications (like Emacs and Geany) have a weird scrollbar issue where the scrollbar slider is drawn but never un-drawn, so if you slide it around pretty soon your whole scrollbar is orange. (I note this here as a precaution and to see if anyone else has the same problem—after all, I did install the theme in a rather wacky fashion)