We bought some foam, fabric, and made a cushion-like object that we attached with Velcro
Magnetic light blocking fabric that was custom made to fit my windows
Installed three Farnier-Peniun sliding windows from Road Paisance. Denim fabric curtains (with insulation) made by a local seamstress.
The blinds were custom made from blackout cloth and standard window rods.
DIY fabric curtains, rolled and tied up when not in use. Velcro to keep in place when down.
Fabric curtains running on threaded pole, velcroed to cabin interior
DIY quilted panels on windows. Connected by magnets.