The end sky texture is rendered upside down behind the starfield texture

The background graphic used for starfield blocks (end portal, end gateway) is the same file used for the end’s sky. This is obvious if you change that texture.

However, unexpectedly, that texture is displayed upside-down compared to its actual appearence as an image file.

Expected behaviour would be for it to be rendered upright, rather than unexpectedly vertically flipped.