Missing resource warnings in game output

The game output log gives warnings for four missing resources:

22:08:35.614
icf
Render thread
Missing resource minecraft:textures/environment/end_sky.png referenced from minecraft:textures/environment/end_sky.png

22:08:35.616
icf
Render thread
Missing resource minecraft:textures/environment/end_flash.png referenced from minecraft:textures/environment/end_flash.png

22:08:35.617
icf
Render thread
Missing resource minecraft:textures/environment/sun.png referenced from minecraft:textures/environment/sun.png

22:08:35.617
icf
Render thread
Missing resource minecraft:textures/environment/moon_phases.png referenced from minecraft:textures/environment/moon_phases.png

These warnings did not appear in Snapshots prior to 25w37a.