11/1/2020: I updated the window a bit. It is now in 3 separate files starting with "Version2". The old file is still there too. The window frame is the same. For the window panes I added stoppers so the windows can't fold in too far. I added another part that is the part of the window that goes on the inside of the house, it has a window sill, I'm going to glue it to the frame. My dollhouse has half-inch thick wood walls, so these fit together perfect for that.

Files:
Version2_Outside_Window_Inset_Frame.stl (this is the window frame)
Version2_Window_Panes.stl (the two window panes that slide up and down and fold out)
Version2_Inside_window.stl (the part of the frame that goes on the inside of the house with a window sill. You can glue it to the inset frame)
EK_Dollhouse_Front_Window_v1_FINAL_ALL.stl (this is the old version, I don't know how to change the file name)
I'm refurbishing the dollhouse my Dad built for my sister 40 years ago. This window fits perfectly my 3" x 4 7/8" x 0.5" depth slot. The lower window opens and closes. All 4 individual window panes swing out (clean all support plastic out of the holes before installing the window panels). Printed on Ender 3: 0.1mm layer, 20% fill, no brim, ~9.5 hours.

Video: https://youtu.be/Z9UMFxrlV6g

Window frame adapted from davidparker98: https://www.thingiverse.com/thing:1704215
Functional swing-open windows by WavyKelp (slightly modified): https://www.thingiverse.com/thing:1720080
Inside window trim adapted from Fotonoska: https://www.thingiverse.com/thing:4616345