Comment # 3 on bug 949983 from Dominique Leuenberger

Some background why this would justify the workaround, if the fix takes too
long to find:

> zypper -n verify
Repository 'openSUSE-Leap-42.1-Oss' is out-of-date. You can run 'zypper
refresh' as root to update it.
Loading repository data...
Reading installed packages...

Problem: nothing provides appdata(firefox.appdata.xml) needed by
application:Firefox-.noarch
 Solution 1: deinstallation of application:Firefox-.noarch
 Solution 2: break application:Firefox-.noarch by ignoring some of its
dependencies

Choose from above solutions by number or cancel [1/2/c] (c): c