gir1.2-gtksource-4 4.8.3-1ubuntu1 (ppc64el binary) in ubuntu lunar

 GtkSourceView is a text widget that extends the standard GTK+ 3.x text widget
 GtkTextView. It improves GtkTextView by implementing syntax highlighting and
 other features typical of a source editor.
 .
 This package contains GObject introspection information.