It is in fact the 'Content Import' app string that needs to be translated. A previous commit errantly included the string 'Content Filter'. But don't remove 'Content Filter'. That is actually a thing in Zap and will eventually make its way to Hubzilla.

Zotlabs/Lib/Apps.php

@@ -328,6 +328,7 @@ class Apps {
 			'Bookmarks' => t('Bookmarks'),
 			'Chatrooms' => t('Chatrooms'),
 			'Content Filter' => t('Content Filter'),
+			'Content Import' => t('Content Import'),
 			'Connections' => t('Connections'),
 			'Remote Diagnostics' => t('Remote Diagnostics'),
 			'Suggest Channels' => t('Suggest Channels'),