Tailwindcss creates additional CSS rules when using class names with decimal fraction

[obecker]

What version of Tailwind CSS are you using?

v3.4.4

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

vite 5.3.3 with postcss 8.4.39

What version of Node.js are you using?

v22.3.0

What browser are you using?

any

What operating system are you using?

macOS

Reproduction URL

https://github.com/obecker/tailwind-issue

Describe your issue

When using size/spacing classes with a decimal fraction (like m-1.5 or size-2.5) then tailwindcss will create extra (unused) rules for the corresponding classes without decimal fraction, i.e. there are also CSS rules for m-1 or size-2 like this (manually formatted for better readability):

.m-1 {
    margin: .25rem
}

.m-1\.5 {
    margin: .375rem
}

.size-2 {
    width: .5rem;
    height: .5rem
}

.size-2\.5 {
    width: .625rem;
    height: .625rem
}

I think tailwindcss should not generate these extra CSS rules.

[wongjn]

Relevant related issue: #9354

[thecrypticace]

Hi! See my response in the above mentioned issue (tl;dr this is intentional in v3): #9354 (comment)

Good news is this should be improved in v4 👍