Can't use % for background-position arbitrary value

[dwkns]

What version of Tailwind CSS are you using?

3.0.23

What build tool (or framework if it abstracts the build tool) are you using?

postcss-cli 9.1.0

What version of Node.js are you using?

v17.7.2

What browser are you using?

Safari

What operating system are you using?

macOS

Reproduction URL
https://play.tailwindcss.com/dBpXEnLlgb

Describe your issue
Percentages are not output when using bg-[ arbitrary values ]
bg-[top_right_75px] → works just fine
bg-[top_right_5rem] → works just fine
bg-[top_right_50%] → doesn't output the expected CSS

Describe the problem you're seeing, any important steps to reproduce and what behavior you expect instead.
https://play.tailwindcss.com/dBpXEnLlgb

Update:
bg-[top_right_calc(50%)] → works just fine!!!!

[RobinMalfait]

Hey! Thank you for your bug report!
Much appreciated! 🙏

This should be fixed by #8015, and will be available in the next release.

You can already try it by using the insiders build npm install tailwindcss@insiders or yarn add tailwindcss@insiders.