Gtk.TextBuffer.prototype.set_modified

function set_modified(setting:Boolean):void {
    // Gjs wrapper for gtk_text_buffer_set_modified()
}

Used to keep track of whether the buffer has been modified since the last time it was saved. Whenever the buffer is saved to disk, call gtk_text_buffer_set_modified (buffer, FALSE). When the buffer is modified, it will automatically toggled on the modified bit again. When the modified bit flips, the buffer emits the Gtk.modified-changed signal.