[v4] Removing default breakpoints not reflected in plugin() API/method

[flx-sta]

What version of Tailwind CSS are you using?

v4.0.1

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

• @tailwindcss/cli 4.0.0
• @tailwindcss/postcss 4.0.0
• postcss 8.5.1

What version of Node.js are you using?

For example: v12.0.0

What browser are you using?

v20.13.0

What operating system are you using?

macOS 14.6.1 (23G93)

Reproduction URL

https://codesandbox.io/p/live/27a50c21-9a15-410a-be6e-f846fdbb6102

Run the build script and check the terminal output.

Describe your issue

When defining my @theme with :

@theme {
  --breakpoint-*: initial;

  --breakpoint-phone: 30rem;
  --breakpoint-tablet: 48rem;
  --breakpoint-default: 75rem;
}

I was expecting for only my custom breakpoints/screens to exist.
But instead it's adding them on top of the existing one when definition a plugin:

{
  sm: '40rem',
  md: '48rem',
  lg: '64rem',
  xl: '80rem',
  '2xl': '96rem',
  phone: '30rem',
  tablet: '48rem',
  default: '75rem',
  __CSS_VALUES__: { phone: 0, tablet: 0, default: 0 }
}
≈ tailwindcss v4.0.1

Done in 113ms

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Unless, is it expected to use the __CSS_VALUES__ object?