Missing category icons with adwaita-icon-theme >= 42

The applications menu looks like this since adwaita-icon-theme 42 (and currently with v43):

Looking at the icons referenced by garcon, the following don't appear to be provided by Adwaita anymore:

1. applications-accessories
2. applications-development
3. applications-games (symbolic used)
4. applications-graphics (symbolic used)
5. applications-internet
6. applications-multimedia (symbolic used, I think this was the same in v41 too)
7. applications-office
8. applications-science (symbolic used)
9. applications-system (symbolic used)

I have a pending downstream bug report about this but I'm not sure how this can be addressed.

Would it be correct and/or possible for garcon to provide suitable category icons? Alternatively, is there an icon theme that distros should recommend for use with Xfce?