On some systems, to_node -> render_texture generates empty or garbled
textures since GTK 4.18 GNOME/gtk#7464. This does not happen when using the cairo
renderer.
Closes#488
This fixes a single case of root being access from the control hide
animation. Apparently it's possible that the widget is unparented from
the window and unmaped but not yet unrefed?
Fixes#473