From Fedora Project Wiki
<summary xml:lang="fr">Un Comic Archive Lecteur</fr>
Is incorrect:
$ appdata-validate .appdata.xml Failed: failed to parse .appdata.xml: Error on line 9 char 54: Element 'fr' was closed, but the currently open element is 'summary'
Should be on my mind:
<summary xml:lang="fr">Un Comic Archive Lecteur</summary>
Hubbitus (talk) 16:43, 7 March 2015 (UTC)
According to the http://people.freedesktop.org/~hughsient/appdata/] the correct metadata license tag for CC0 is CC0-1.0.