libgtksourceview-4-0 4.8.4-4 (armhf 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 the shared libraries required by applications to use
 this widget.