Steps causing the bug to occur:
- Run @jersmi's composition FullscreenImageSize.vuo from Fullscreen Image Weirdness.
- Resize the window...
- Go fullscreen and back – the window size toggles between the expected size (1024x768) and a wrong size (1024x571).
- Or resize with the mouse — the window size sometimes cycles between two or more sizes a few pixels apart.
I checked that the output of
Render Layers to Image has the size specified by its Width and Height ports. So it looks like the window from
Render Image to Window isn't always the same size as the input image. Or
Get Window Dimensions is outputting the wrong size.