Comment # 5 on bug 1158839 from Fabian Vogt

(In reply to Nathaniel Graham from comment #4)
> IIRC `appstreamcli validate` is preferred over `appstream-util validate`.

AppStream(-Qt) vs. appstream-glib, both have to work anyway...

> Nevertheless, you're right, the file has an error in it. I've just corrected
> it with
> https://commits.kde.org/plasma-sdk/d5f44659ae4119879326646bfb2570232946180b.

Plasma/5.17 as well?

> Would you be able to regenerate the AppStream data in openSUSE with this
> commit included? Thanks!

That happens automatically once the package ends up in TW.
I can submit a patch once it's fixed in git.