SunRed [1] filed a request to merge lib32-libdbusmenu-gtk2 [2] into lib32-libdbusmenu [3]:

For easier maintaining this should be merged into the split package 'lib32-libdbusmenu'. After that, I am able to update the main package.

[1] https://aur.archlinux.org/account/SunRed/ [2] https://aur.archlinux.org/pkgbase/lib32-libdbusmenu-gtk2/ [3] https://aur.archlinux.org/pkgbase/lib32-libdbusmenu/