Extra word in plural form creates duplicated words in sentence
In src/fragments-utils.vala is the following code for counting time left for a torrent.
var str_days = ngettext ("%u day", "%u days left", days).printf (days);
var str_hours = ngettext ("%u hour", "%u hours left", hours).printf (hours);
var str_minutes = ngettext ("%u minute", "%u minutes left", minutes).printf (minutes);
var str_seconds = ngettext ("%u second", "%u seconds left", seconds).printf (seconds);
if (days > 0) return "%s, %s".printf (str_days, str_hours);
if (hours > 0) return "%s, %s".printf (str_hours, str_minutes);
if (minutes > 0) return "%s".printf (str_minutes);
if (seconds > 0) return str_seconds;
However the word "left" is added to the plural forms. The (hours > 0) case will then create strings like "4 hours left, 16 minutes left" since the two strings are concatenated.