It seems like in several cases detection is added for a desktop environment then a action is added to say xdg-open but not xdg-su or xdg-terminal, this causes them to fail rather then using the generic option as they would have in the past.
xdg-su and xdg-terminal are both broken in this way on enlightenment as the support is detected for xdg-open but nothing is specified for the other cases.
The following patch https://build.opensuse.org/package/view_file/X11:common:Factory/xdg-utils/fix-enlightenment-support.patch?expand=1 fixes and enhances enlightenment support by using enlightenments terminal emulator (terminology) rather then xterm.
When i was looking at this issue in more detail it seemed like mate suffered from a similar issue in atleast 1 tool but all should probably be checked to see they have a action for each tool, if not they need to run the generic tool.
(Yes, these could probably use a lot more love, there's a reason they're not enabled by default).
Can you attach the bug please?
It's not clear to me how to extract the raw patch from the link you provided.
Created attachment 112114 [details] [review]
fix enlightenment patch
Sorry the link is on the previous page, attached now
I'm lowering the importance to minor because these tools aren't really part of xdg-utils since they are not installed by the build system.
Regarding xdg-su, shouldn't it be deprecated in favour of PolicyKit?
xdg-terminal could be useful though.