When you click Add on the Management > Linguistic Tool Setup > Filter Groups Setup > Filter Group: <group> page, the Add Filter Group Entry dialog appears. You specify a MIME type, a filter, and a filter configuration for the entry.

When the value of the Filter selection for a MIME type is “Not Translatable”, the “Filter Configuration” column is blank for that entry. If the filter resolution process finds that a MIME type is set to “Not Translatable,” it treats assets of that MIME type as not translatable.