In the new sprites directory, there is a folder called bundle which only has background.png.mcmeta in it. An additional folder under sprites/container/bundle houses all the bundle texture files, including one titled background.png, which I believe is the file of interest for that mcmeta file.

In a discussion in Slicedlime's discord server, Gegy stated this looks like a bug.

(link to discussion message for reference: https://discord.com/channels/173877869640941568/381490427255324672/1136361154214625330)

Steps to Reproduce:

1. Open the game jar file with an archive software (or copy the jar and add .zip after the file extension and open like a zip file)
   • On windows, run Win + R and enter %appdata%\.minecraft\versions\<version> into the text box to navigate to the game jar
     • Replace <version> with the affected version in question
2. Navigate to assets/minecraft/textures/gui/sprites
3. Look for a bundle folder
   • Observed: such folder exists and houses the mcmeta file
   • Expected: such folder would not exist, only sprites/container/bundle and the mcmeta file would be there in it