[system] Remove prefix

[oliviertassinari]

Summary

As far as I know, prefixes are no longer needed for the last 12+ months. I don't know any of https://mui.com/material-ui/getting-started/supported-platforms/#browser that requires it.

Now, considering that those are pure pain from a DX perspective. e.g. -webkit-box-pack 🤡

https://mui.com/material-ui/react-button/

and bundle size. https://pkg-size.dev/stylis

I think it's time we remove them.

• Remove outdated prefixes thysultan/stylis#334
• Remove outdated fallbacks thysultan/stylis#338

Now, to test whether this is true or not. If we can't do it right now, to move to v7. cc @brijeshb42

Examples

emotion-js/emotion#3296

Motivation

Stay relevant.

Search keywords: -

[siriwatknp]

I believe nothing to do on our side since the prefixer is used internally by Emotion. There is a PR to remove it in Emotion v12.

User can opt-out from prefixer in v6 by provide a custom cache.stylisPlugins.

[oliviertassinari]

@siriwatknp It's a breaking change for emotion, it might take some time before they make the change.

In any cases, we have to also remove this because we tell people in our docs to add the prefixer.

Now, if it's not a breaking change for us and we have to do work anyway. Why not work on this now, as a quick win?

[aarongarciah]

After looking into this, we can't stop passing prefixed to the stylisPlugins option from createCache because some CSS properties still need to be prefixed even in modern browsers (e.g. user-select in Safari 18.3). Emotion uses its own prefixer (a more minimalistic version of the stylis one), but only when no stylisPlugins option is present (see https://github.com/emotion-js/emotion/blob/8dc1a6dd19d2dc9ce435ef0aff85ccf5647f5d2e/packages/cache/src/index.ts#L89).

Today, users get a different output when using Emotion as is vs passing stylisPlugins: [stylisPrefixer], because the Emotion's prefixer has diverged over time from the stylis one.

We'll reach out to the Emotion team to see if there's an estimated schedule for when emotion-js/emotion#3296 will land (v12) or if the changes can be backported to v11 in an opt-in way.

[aarongarciah]

Emotion doesn't have a tentative timeline for Emotion v12 just yet. They're open for ideas on how to backport the prefixer simplification to v11 in a retro-compatible way. More info: emotion-js/emotion#3314 (comment)