css: stop printing the `:-moz-any()` copy for Firefox 78, and regenerate the vendor prefix table from one caniuse-lite copy by robobun · Pull Request #45945 · oven-sh/bun

robobun · 2026-10-18T17:02:14Z

Problem

With the default targets, each rule with :is() or :not(a, b) prints a :-webkit-any() copy for Chrome 80 and a :-moz-any() copy. Firefox 78 has :is(). src/css/prefixes.rs took the end from Firefox for Android (79).
The table ends 42 ranges at the newest browser its data knew (no -moz-available for Firefox 133): src/css/build-prefixes.js took "the newest version" from a second caniuse-lite copy. Only bun:internal-for-testing reaches it.

Fix

Commit 1: the generator reads the caniuse-lite copy of autoprefixer and regenerates the table on lightningcss 1.32.0's data. Default output is the same.
Commit 2: an Android record of MDN no longer ends the range of a desktop browser: :-moz-any() ends at Firefox 77. Default builds keep the :-webkit-any() copy.
Verified: test/js/bun/css/css.test.ts (20 new cases, 14 fail on bun 1.4.2) and two changed snapshots. Also test/js/bun/css/, test/bundler/css/, test/bundler/esbuild/css.test.ts.
Self-reviewed: 23 concerns raised, 13 addressed, 9 moved to the range-rule follow-up. Rejected: a generator drift test (Notes).

Background

Feature::prefixes_for maps a feature and the targets to vendor prefixes.
Considered porting the lightningcss 1.32.0 table: the generator cannot emit it, and it has the same :-moz-any() range (3 ranges differ, see Notes).
Question for a maintainer: Safari 15.3 gets no -webkit-mask-image (caniuse entry "15.2-15.3"). A follow-up ends each range before the next listed version, like esbuild, and departs from lightningcss in 786 ranges. Is it wanted?

Downsides

Default output changes. Minified bulma.css goes from 761,870 to 735,742 B, pico.css from 136,146 to 113,988 B.
src/css/compat.rs (same generator) is not regenerated (Notes).
Targets::prefixes is 8,613 B (main 8,696 B).

Notes

No issue exists for the stale ranges. I found them by a comparison with lightningcss. A release build uses only the default targets, and no range changes its answer there. #40368 (cssTarget) makes newer targets reachable, so the refresh must land before it.

Regenerate

The three data packages are not dependencies of the repository. Install them in a scratch directory:

mkdir /tmp/prefix-data && cd /tmp/prefix-data && echo '{}' > package.json
bun add autoprefixer@10.4.27 caniuse-lite@1.0.30001777 @mdn/browser-compat-data@7.3.6
cd <repo> && NODE_PATH=/tmp/prefix-data/node_modules bun src/css/build-prefixes.js prefixes

lightningcss 1.32.0 pins these versions. The header of prefixes.rs names them. The prefixes argument writes only prefixes.rs. A second run changes nothing. On main the generator throws on this data.

A run with no argument, or with compat, stops before it writes a file. The new compat.rs has no MozAvailableSize, and the generator does not drop a variant that Rust code in src/css still names.

Cause of the stale ranges (commit 1)

build-prefixes.js read "the newest version of each browser" from require("caniuse-lite") and the versions that need a prefix from autoprefixer/data/prefixes. autoprefixer loads its own caniuse-lite. A range had no upper bound only when the newest version was in the list.
Various CSS fixing and stability stuff #16889 (f6ec0da) regenerated the table. Its bun.lock had caniuse-lite@1.0.30001695 at the top level and caniuse-lite@1.0.30001653 under autoprefixer. The newest browsers of 1.0.30001653 are Safari 18.0, Firefox 132, Chrome 130, Edge 127 and Samsung 25: the upper bounds in the table on main.
With two copies today (top level 1.0.30001816, autoprefixer's 1.0.30001777) the old read leaves 45 of 963 ranges without an upper bound. The new read gives 71, the same as an install with one copy.
lightningcss had the same defect at its data commit of 2024-09-10 for Chrome 130 and Edge 127: its lockfile had two caniuse-lite versions.

The :-moz-any() range (commit 2)

MDN has a record for a desktop browser and one for its Android variant. Both feed one column. The end was the later of the two.
Firefox has :is() from 78. Firefox for Android has it from 79, and MDN lists no release of it from 69 to 78. compat.rs already says Firefox 78 for :is().
lightningcss 1.32.0, 1.33.0 and its main branch have the same range (version <= 78.0).
An Android record now ends a range only when the desktop record gives no end. One range changes: AnyPseudo for Firefox, <= 78.0 to <= 77.0.
Targets::prefixes has no rule for a version between two listed ones. A target of Firefox 77.0.1 gets no copy now. No target string can name a patch release.
The 15 stylesheets in test/js/bun/css/files/, minified with the default targets: 2,732,962 B to 2,656,844 B (-2.79 %). bulma.css 761,870 to 735,742 B, pico.css 136,146 to 113,988 B, uikit.css 270,923 to 269,219 B. 11 sheets do not change.
docs/bundler/css.mdx showed the :-moz-any() copy in three examples. They now show what a default build prints.

The 3 ranges that differ from lightningcss 1.32.0

AnyPseudo for Firefox: <= 77.0 (lightningcss <= 78.0).
BackgroundClip for Safari <= 13.1 and iOS <= 13.4 (lightningcss <= 13.0 for both). These are the ends the table on main has. caniuse dropped the prefix flag for Safari (Mark background-clip: text as fully supported + correct history of Safari support Fyrd/caniuse#7204). MDN says that only -webkit-background-clip takes text before Safari 14.
The other 960 ranges are equal.

Question for a maintainer, in detail

A range ends at the first version of the last caniuse entry that needs the prefix. An entry can be a range of versions ("15.2-15.3"), and caniuse lists no patch release.
Targets::prefixes replaces the prefixes that the author wrote with the answer of the table. So a short range also removes a declaration: -webkit-transform: rotate(1deg); transform: rotate(1deg) becomes transform alone for iOS 8.4 (entry "8.1-8.4").
The follow-up ends each range before the next version that caniuse lists (version < 15.4). esbuild stores the same bound: withoutPrefix in its internal/compat/css_table.go.
Against this PR, 786 of 892 bounded ranges end later, 0 end earlier and no lower bound moves. Default output does not change.
lightningcss 1.33.0 ends Stretch for Safari at 26.5. Safari 26.6 needs the prefix on newer data. The follow-up gives version < 27.0.
The change is written and tested. I open it after this PR merges, or earlier if a maintainer asks.

Measurements

Release binary (bun run build:release, nm -S and the linker map, main 017b243 against this PR): Targets::prefixes is 8,613 B (main 8,696 B). Its jump table is 1,440 B (main 1,440 B). bun is 106,911,456 B (main 106,911,456 B).
Calls to Targets::prefixes: 45 sites (main 45). FlexHandler::flush 5,172 B, AlignHandler::flush 6,356 B, BorderRadiusHandler::flush 8,033 B (main 5,172 / 6,356 / 8,033 B).
Instructions per lookup at the default targets: mean 77.11 (main 77.09). Branches: 7.23 (main 7.26). These are perf_event_open counters over the 184 features, in an isolated build of the table.
Prefix sets that change at the default targets: 1 of 184 (AnyPseudo loses -moz-, from commit 2). At the defaults that css: bump the default browser targets to Vite's baseline widely available set #40369 proposes: 0 of 184.
Against main: 46 ranges in 15 features differ. The table has fewer prefixes in 6 places: :-moz-any() at Firefox 78, -webkit-box-decoration-break at Chrome 130 (which has the property without a prefix), and 4 Android ranges between 4.4.4 and 127 (Stretch, BoxDecorationBreak, ColorAdjust, PrintColorAdjust, as in lightningcss). No Bun target syntax names Android.
Generator: a second run changes 0 lines. A prefixes run writes 1 file. cargo fmt --all -- --check and bun fmt --check are clean.
Emitted tests: version <= 347 to 326, version == 3 to 3. 75 match arms before and after.
Tests: 20 new cases in css.test.ts. 14 fail on bun 1.4.2 and all pass on the debug build (1334 pass, 0 fail). The two changed snapshots (is-selector-21169.test.ts, 25794.test.ts) fail on bun 1.4.2.

Not in this PR

compat.rs. The generator's compat output on this data equals the compat table of lightningcss 1.32.0 in all 213 shared rows. It must not be checked in as it is, and the generator now refuses to write it. It drops MozAvailableSize, which properties/size.rs:173 and :309 use. It moves 22 Android cells from 131 to 145, the newest WebView and not a support version. It makes WebkitFillAvailableSize unsupported for Chrome, Edge and Opera.
compat.rs has the Android number in its Firefox column too. 8 rows say Firefox 79 where Firefox has the feature earlier: min(), max(), clamp() (75), ::part() (72), font-size: xxx-large (70), text-decoration-thickness percentages (74), the text-decoration shorthand with a thickness (70) and list-style-type: none (1). The MDN loop of the generator (browserMap[name] = v) keeps the last record of a column, and firefox_android comes after firefox. webview_ios now maps to ios_saf too and comes after safari_ios, so the compat refresh must give one record precedence there as well. The self-review asked for a tracking issue. I cannot file one, so the cause is here.
TextSizeAdjust gives -moz- to each Firefox version, from the Firefox for Android entry of caniuse alone. Desktop Firefox has no text-size-adjust. No handler on main reads this range. css: write the vendor prefixes for user-select, appearance, hyphens and five more properties #45814 adds one.
css: write the vendor prefixes for user-select, appearance, hyphens and five more properties #45814 also splits the PrintColorAdjust | ColorAdjust arm: a generator change, and a table edit on the old data with the Chrome 130 bound. This PR changes the same arm (Chrome 135). The PR that lands second must regenerate the table.
7 ranges have no end only because a mobile list of caniuse is at its newest version (op_mob 80 keeps Stretch for Opera open). The effect is an unneeded prefix. lightningcss has the same ranges.
No test checks that prefixes.rs is the output of the generator. The self-review asked for one. It needs a checked-in copy of the range data and a generator that takes it as input, so I left it for the follow-up. No CI job runs the generator.
The compat part of the generator throws on @mdn/browser-compat-data 8.1.6. lightningcss has the same code.
The data of lightningcss 1.33.0 adds the variants MaskPositionX and MaskPositionY. Newer data adds InitialLetter.
12 of the 15 refreshed features have no property handler on main. Only stretch, background-clip and :is() show in output today.

Suites

bun bd test on each file of test/js/bun/css/, on test/bundler/css/, test/bundler/esbuild/css.test.ts, test/js/bun/http/bun-serve-html.test.ts, test/regression/issue/{25785,25794,27458,27598}.test.ts and the two css-system-color-* tests. css-fuzz.test.ts times out on my debug build with and without this change.

build-prefixes.js read the newest version of each browser from the top-level caniuse-lite. It read the versions that need a prefix from autoprefixer, which loads its own copy of caniuse-lite. A range has no upper bound only when the newest version is in that list. With two different copies it never is, so each such range ended at the newest browser of the older copy (Safari 18.0, Firefox 132, Chrome 130). The generator now reads caniuse-lite through autoprefixer's resolution. It also has the data-collection changes of lightningcss 1.32.0 (webview_ios, entries for `background-clip: text` in Safari, the MDN 7 paths), emits the file as it is checked in (pub(crate), is_some(), rustfmt with the workspace edition), names the data versions in the header, and takes the outputs to write as arguments. prefixes.rs is the output of `bun src/css/build-prefixes.js prefixes` on autoprefixer 10.4.27, caniuse-lite 1.0.30001777 and @mdn/browser-compat-data 7.3.6, the versions that lightningcss 1.32.0 pins. Each range is equal to the range in lightningcss 1.32.0, except `background-clip: text` for Safari and iOS. lightningcss ends those two at 13.0. The table keeps the ends that it had: 13.1 and 13.4.

MDN has a record for a desktop browser and one for its Android variant, and both feed one column of the table. The end of a `:-webkit-any()` or `:-moz-any()` range was the later of the two. Firefox has `:is()` from 78. Firefox for Android has it from 79, its first release after 68. So the range included Firefox 78, which the default targets have. Each rule with `:is()`, `:not(a, b)` or a lowered logical property got a `:-moz-any()` copy that no target browser needs. A mobile record no longer ends the range of a column whose desktop record gives an end. One range changes: AnyPseudo for Firefox ends at 77. With the default targets the `:-moz-any()` copy is gone. The `:-webkit-any()` copy stays, because Chrome 80, Edge 80 and Opera 67 have no `:is()`.

robobun · 2026-10-18T17:02:26Z

^{Updated 2:52 AM PT - Oct 20th, 2026}

✅ @robobun, your commit 2ee5ae5605ec5afe6a5164f3d5871b7b4303d965 passed in Build #129306! 🎉

🧪 To try this PR locally:

bunx bun-pr 45945

That installs a local version of the PR into your bun-45945 executable, so you can run:

bun-45945 --bun

robobun · 2026-10-18T17:02:47Z

Status

Reproduced on bun 1.4.2:

// BUN_FEATURE_FLAG_INTERNAL_FOR_TESTING=1 bun repro.js
const { cssInternals } = require("bun:internal-for-testing");
const defaults = { chrome: 80 << 16, edge: 80 << 16, firefox: 78 << 16, safari: 14 << 16, opera: 67 << 16 };
console.log(cssInternals.prefixTest("a:is(.b,.c){color:red}", "", defaults));
console.log(cssInternals.prefixTest(".a{width:stretch}", "", { firefox: 140 << 16 }));

The first call prints three rules (:-webkit-any, :-moz-any, :is). The second prints width: stretch with no -moz-available.

This PR is closed. Its :-moz-any() part is on main through #47025 (7942008): there, the first call prints two rules (:-webkit-any, :is). The table regeneration is not on main, and the second call prints the same as on bun 1.4.2.

coderabbitai · 2026-10-18T17:09:53Z

Walkthrough

The CSS prefix generator now reads updated compatibility data, supports selective output generation, and emits revised browser-version prefix rules. Tests cover stretch, background-clip, and :is() prefixing. Documentation and regression snapshots remove specified :-moz-any() fallbacks.

Changes

CSS Prefix Updates

Layer / File(s)	Summary
Compatibility data generation `src/css/build-prefixes.js`	The generator reads Caniuse data from Autoprefixer’s dependency context and uses updated MDN data paths. It supports selecting `targets`, `prefixes`, or `compat` output, records data versions, and adjusts generated browser checks.
Generated browser-prefix rules `src/css/prefixes.rs`	The compatibility data version and browser-version ranges changed across multiple CSS properties, including `BackgroundClip`, `Stretch`, `TextSizeAdjust`, and `AnyPseudo`.
Prefix expectations and documentation `test/js/bun/css/css.test.ts`, `test/bundler/css/is-selector-21169.test.ts`, `test/regression/issue/25794.test.ts`, `docs/bundler/css.mdx`	Tests add prefix expectations for `stretch`, `background-clip: text`, and `:is()`. Updated snapshots and documentation remove specified `:-moz-any()` fallback examples.

Suggested reviewers: jarred-sumner

Priority: ➖ Normal

Merge Risk: 🟡 Moderate · up to 3c56e

Regenerating the CSS tables can leave the next Rust build unable to compile. Preserve the compatibility entry or update its consumer before merging.

Pre-merge checks: 4

Check name	Status	Explanation
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Title check		The title clearly identifies both main changes: removing the Firefox 78 `:-moz-any()` output and regenerating the vendor prefix table from one `caniuse-lite` copy. It is longer than necessary but rema…
Description check		The description provides detailed problem, fix, verification, background, limitations, test results, and follow-up information. It does not use the template headings exactly, but it fully covers the r…

Full details: Title check

Explanation

The title clearly identifies both main changes: removing the Firefox 78 :-moz-any() output and regenerating the vendor prefix table from one caniuse-lite copy. It is longer than necessary but remains specific and relevant.

Full details: Description check

Explanation

The description provides detailed problem, fix, verification, background, limitations, test results, and follow-up information. It does not use the template headings exactly, but it fully covers the required purpose and verification details.

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Inline comments:
Review comments at @src/css/build-prefixes.js:
- Around line 524-540: Update the generated compatibility data and its consumer
so the no-argument generator run keeps `F::MozAvailableSize` available to
`size.rs` and does not break the Rust build. Preserve `MozAvailableSize` in
`compat.rs`, or update `size.rs` to use the replacement supported by the new
compatibility inputs.

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docs/bundler/css.mdx
src/css/build-prefixes.js
src/css/prefixes.rs
test/bundler/css/is-selector-21169.test.ts
test/js/bun/css/css.test.ts
test/regression/issue/25794.test.ts

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docs/bundler/css.mdx
test/regression/issue/25794.test.ts

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…s in use On current data a run with no argument, or with `compat`, wrote a compat.rs without `MozAvailableSize`. `properties/size.rs` uses that variant, so the crate did not compile after the run. The generator now compares the variants it is about to write with the variants in the file. It stops with an error when Rust code in src/css still names a variant that would go away. The same check covers prefixes.rs.

claude

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

Beyond the inline findings, I also checked the other regenerated ranges that moved against the base table — the TextDecoration cap at Safari/iOS 26.0, the now-unconditional -moz-text-size-adjust for Firefox, and the BackgroundClip lower bounds at Safari 3.1 / iOS 4.0 — and each follows from the declared caniuse-lite 1.0.30001777 data plus the hand-pushed background-clip entries in src/css/build-prefixes.js, not from a generator defect. The default-target output changes only for AnyPseudo, as the new css.test.ts cases cover.

Extended reasoning...

The change reworks the CSS vendor-prefix table generator (src/css/build-prefixes.js) to read caniuse-lite through autoprefixer's resolution, adds a mobile-record rule for the any-pseudo range, adds CLI output selection and a variant-drop check, and regenerates src/css/prefixes.rs with many range changes; tests and docs are updated to drop the :-moz-any() copy. No security-sensitive surface is touched. Four inline findings (android range caps, Firefox 77 patch-release gap, the compat.rs sibling of the mobile-record rule, and the no-argument generator run failing after partial writes) already signal that a human should weigh the range-rule decisions, so this body only records what else was examined and ruled out.

Additional findings (outside the current diff — GitHub can't attach inline comments there):

🟣 src/css/build-prefixes.js — Pre-existing sibling of the :-moz-any() fix: the compat table still lets an Android MDN record overwrite the desktop column, so Firefox 72-78 (the default firefox78) is told it lacks ::part, clamp(), min(), max(). The loop at src/css/build-prefixes.js:446-447 assigns browserMap[name] = v per MDN key with no minimum, so firefox_android (79) replaces firefox (72/75), and the new webview_ios mapping now does the same to safari_ios on the next compat run. Fix: give the desktop record precedence (or take the minimum) wherever two MDN keys map to one column, as anyPseudoVersions now does, then regenerate compat.rs.

Why this was flagged

The checked-in src/css/compat.rs shows the effect today: PartPseudo (compat.rs:439), ClampFunction (compat.rs:316) and MinFunction (compat.rs:422) all carry firefox = 5177344 (79.0), although MDN gives Firefox 72 for ::part and 75 for clamp()/min(); 79 is the Firefox for Android value, which wins because BCD lists firefox_android after firefox and src/css/build-prefixes.js:447 overwrites rather than keeps the lower version. With the default targets (firefox78 in src/css/targets.rs:194), src/css/rules/mod.rs:669-700 therefore treats a selector list containing ::part() as incompatible and wraps or splits the rule, and src/css/properties/size.rs:456-461 keeps a fallback declaration before a clamp() value. The base branch has the same loop, so this is pre-existing, but the diff fixes the identical mobile-overrides-desktop defect only for the any-pseudo prefix range and adds webview_ios: "ios_saf" (src/css/build-prefixes.js:41), a second mobile writer that this loop will let overwrite the safari_ios value on the next compat run.

Verification: src/css/build-prefixes.js:446-447 does name = MDN_BROWSER_MAPPING[name] || name; browserMap[name] = v;, a plain overwrite, no Math.min, so firefox_android (mapped to firefox at :38) replaces firefox whenever the Android record is newer. src/css/compat.rs:316, :422, :418 and :439 all have firefox = 5177344 = 79.0, the Firefox for Android value. The base branch has the same compat.rs and the same loop, hence pre-existing.

A run with no argument wrote targets.rs and prefixes.rs and then stopped at the check for compat.rs. Both checks now run before the first write, so a run that fails changes no file.

robobun · 2026-10-20T04:54:22Z

Follow-up to the review above:

The run with no argument (build-prefixes.js:679): fixed in 2ee5ae5. Both checks now run before the first write, so a run that fails changes no file.
The Android ranges and the end at Firefox 77.0.0: answered in the threads. Both need a rule for a version between two caniuse entries. That rule is the follow-up that the PR body asks a maintainer about.
compat.rs (outside the diff): correct, and not changed here. The PR notes name the loop (browserMap[name] = v) and the 8 rows that have Firefox 79. The point about webview_ios is new, and I added it to the notes: it now maps to ios_saf and comes after safari_ios, so the same loop lets it replace the safari_ios value. The generator stops a compat run on the current data, so this PR cannot write such a table.

claude

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

Beyond the inline finding, I also checked two things in this push: the three removed :-moz-any() expectations (docs/bundler/css.mdx, test/bundler/css/is-selector-21169.test.ts, test/regression/issue/25794.test.ts) follow directly from the AnyPseudo firefox arm ending at 77 with the default firefox 78 target, so they are not a weakening; and narrowing prefixes_for/is_flex_2009/is_webkit_gradient to pub(crate) is safe because every caller lives inside the src/css crate (no src/css_jsc use). The checkVariants calls now run before any write, which closes the ordering point raised on the earlier push.

Extended reasoning...

The push adds commit 2ee5ae5 moving checkVariants ahead of the first file write, plus the generator and table changes from the earlier push. The removed test/docs expectations trace to one changed range, and the visibility narrowing has no out-of-crate callers; the remaining optional range-rule points from the prior review are unchanged and left to the author's stated follow-up.

@mikamikasuki

### What does this PR do? Consolidates the open pull requests on the CSS parser (`src/css`: parsing, minifying, lowering, printing, CSS modules) into one. 179 open pull requests were in scope. Each was judged by one rule: **the output must mean to a browser what the input meant.** Every claim was run through a build of `main`, a build with the change, lightningcss 1.33 and Chromium 156 (CSSOM, computed values, painted pixels for colors and gradients), and counted against 10,116 real stylesheets: the published CSS of about 190 popular npm packages, plus stylesheets from open source repositories. 107 land here, whole or in part, most of them cut down. The source diff is net negative. Of the 10,116, 9,509 are stylesheets that someone ships. The rest are test fixtures of other tools (521), Tailwind v4 source that needs its plugin (59) and SCSS, PostCSS or template source (27). | 9,509 shipped stylesheets | `main` | this branch | |---|---|---| | fail to build | 71 | 35 | | ... of those, valid CSS that Bun rejects | | 0 | | minified output reads differently in Chromium than the input | 552 | 2 | | CSS modules with a name that is referenced but not defined, or exported but not defined | 166 | 0 | | all 10,116 | `main` | this branch | |---|---|---| | fail to build | 192 | 141 | | minified output reads differently in Chromium than the input | 593 | 15 | | build on `main`, fail here | | 0 | | right on `main`, wrong here (minified, and at the default targets) | | 0 | | size of the minified output, no targets | 162.32 MB | 162.47 MB (+0.093%) | | size of the output at the default targets | 224.1 MB | 210.2 MB (-6.2%) | A syntax error is a build error, with one exception: the IE star hack `*zoom: 1` is skipped, because tachyons and handsontable ship it. The 35 shipped stylesheets that fail are invalid CSS: 28 have a selector that Chromium drops (semantic-ui-css, swiper, @ionic/core, Adobe Spectrum, xp.css), 2 an `@import` after other rules, and one each `@supports not X and Y`, a nested `@keyframes`, a stray comma, a selector list in `::slotted()`, `@media screen\0` (govuk-frontend). The 2 that read differently fold a `color-mix()` inside a gradient (see the known gaps). The growth of the minified output is rules and declarations that `main` deleted by mistake: 87 KB of rules, 45 KB of prefixed declarations that only browser targets can rule out. #### Popular CSS that `main` breaks today - normalize.css, modern-normalize, sanitize.css: `font-family: monospace, monospace` is collapsed to `monospace`, which changes the font size from 16px to 13px (#46662). - CKEditor 5, Tabler, Carbon, VitePress, Ionic, PatternFly, Excalidraw: a rule of custom properties is deleted as a "duplicate" of a later rule with the same selector and other custom properties. 37 stylesheets lose 1,681 custom properties (#33684). - Material Components, daisyUI, DocSearch, plyr: a `var()` size loses to its own fallback (#42101). - nextra, daisyUI, CKEditor: declarations written after a nested rule are moved above it (#45462). - antd 4, purecss, govuk-frontend: browser hacks in selector lists start to apply everywhere (#42100). - foundation-sites, flatpickr, 98.css, blueprintjs, scalar, react-datepicker: the build fails on valid CSS (#46756, #38552, #38534). tachyons, handsontable: it fails on the IE star hack (#46751). - nodejs.org, Mantine: a CSS module exports classes that no rule defines, because the `@apply` or `@mixin` in them is moved out of the rule (#46759). - hint.css and 42 more: `z-index: 1000001` and `1000000` become the same number (#46715). - Adobe Spectrum: `--version: 5.0.1` prints as `5.1`. - A quarter of all stylesheets: minified output has a stray space in `align-items: center` (#41993). #### Behavior changes to look at first 1. **`light-dark()` is kept as written at the default browser targets** (#42009). The lowered form `var(--buncss-light, a) var(--buncss-dark, b)` is invalid unless a compiled `color-scheme` covers the element: 184 of the 215 real stylesheets that get it never define the variable, so every browser drops the declaration. The docs section on the polyfill is removed. 2. **`border` is not built from longhands** (#42072): `border-width:0;border-style:solid;border-color:red` stays three declarations, because `border` also resets `border-image`. 305 real stylesheets grow by 30 KB in total; `bootstrap.min.css` by 113 bytes, 5 gzipped. No real stylesheet was found where the old merge shows, so this is the one to drop if size matters more. 14 existing expectations change. 3. **A CSS module no longer exports names that only occur inside `:global(...)`** (#45487). 73 real modules lose 202 export keys, all of them names that no rule has. `import { g }` or `composes: g` of such a name becomes a build error. 4. **Container names and `@counter-style` names stay global in a CSS module** (#45247 by @mikamikasuki). `main` hashes the `@container` name but not `container-name`, so a named query never matches. postcss-modules (Vite, css-loader, Next.js) keeps them global; lightningcss and esbuild hash both. Global keeps a container that is queried from another file or from JS working. 5. **Syntax errors are build errors, also two that `main` lets through**: a media query that stops short (`@media screen and {`, `@media not {`, `@import "a.css" screen and;`) and `@media (width <) foo {`. No stylesheet of the 10,116 has either. A condition that is valid by the grammar though no browser knows it, `( ... )` or `fn( ... )`, is kept as written (#46756): `(min-width:0\0)`, `(not(hover))`. 6. **Declarations after a nested rule stay where they were written**, as a nested declarations rule (#45462). Changes the output of 199 real stylesheets; in a fuzz of 2,850 nested programs compared by computed style, `main` was wrong in 1,056 and the pull request's code, before it was trimmed here, in none. 7. **`Bun.color`**: `color()` inputs are converted instead of returned as a string (`Bun.color("color(srgb 1 0 0)", "hex")` was `"color(srgb 1 0 0)"`); `currentColor`, system colors and `light-dark()` give `null` in the converting formats instead of the keyword as a string; a relative color or `color-mix()` outside sRGB is clipped, not gamut-mapped (`hsl(from oklch(100% .399 336.3) h s l)` is `#ff5bff`, was `#fff`). 8. The `:-moz-any()` and `:-webkit-any()` copies of rules with `:is()` are gone at the default targets (#45945, #42029). The `:-webkit-any()` copy outranked the original rule: `.title{color:blue} :is(h1,h2,h3){color:red}` painted red. 5.8% of all default-target output was the `:-moz-any()` copies. 9. `Property` grows from 216 to 224 bytes: `Url` stores its text as a slice so that two `url()` values can be compared (#46895). The pull request packed a pointer and a `u32` behind `unsafe` to avoid that. #### Not in this PR, needs a decision - **Raise the default browser targets (#40369) and add a `cssTarget` option (#40368).** Today: Chrome 80, Edge 80, Firefox 78, Safari 14, Opera 67, and no public way to change them. At Vite 8's floor the output of the 9,924 stylesheets is 15.3% smaller (3.9% gzipped). About a dozen fixes here only matter at today's floor, and code for older targets is unreachable without the option. - Vendor prefixes for `user-select`, `appearance`, `hyphens` and five more (#45814): 1,116 real stylesheets lack a prefix they need at the default targets. And for `backdrop-filter` (#44648): 173. - Clip instead of gamut-map in the sRGB fallback of a plain wide-gamut color: deletes about 90 lines, changes every pinned fallback hex. If the mapping stays, #44647 by @oddharsh makes it closer to what browsers paint (colors off by 2/255 or more: 168 to 110 of 3,170 real ones). #### Changes **Rules: duplicates, merging, nesting, fallbacks** - The `:-moz-any()` copy of every rule with `:is()` or `:not(a, b)` is gone: Firefox 78 has `:is()` (#45945). 1,164 real stylesheets - Keep declarations written after a nested rule in place with a nested declarations rule (#45462). 379 real stylesheets - With nesting compiled away, an unknown at-rule inside a style rule was moved out of it: `.wrapper{@apply flex}` printed a bare `@apply flex;` and the rule was gone, so a CSS module exported a class that no rule defines. It now stays in a block under the compiled selector. 72 real modules with Tailwind's `@apply`, 25 with Mantine's `@mixin` (#46759). 316 real stylesheets - Keep !important in the rules generated for logical properties and color-scheme (#38597). 311 real stylesheets - With browser targets, remove an earlier duplicate rule only when its declaration block is equal (#46861). 171 real stylesheets - Compare custom property names in `PropertyId` equality and importance in duplicate-rule detection (#33684). 40 real stylesheets - Keep same-condition @supports rules and empty named @layer blocks (#46733). 31 real stylesheets - Keep target-added vendor prefix passes on cloned and re-minified rules, and never print a bare `:full-screen` (#43339). 12 real stylesheets - Keep the selectors on rules added for color fallbacks and logical properties (#43240). 3 real stylesheets - A later declaration of a property drops the `@supports` color copies of the earlier one, which printed after the rule and won (#45560). 2 real stylesheets - Do not merge style rules in a stylesheet that holds `revert-rule` (#46953). 1 real stylesheets - `@import ... supports(-webkit-mask: none)` kept its prefix (#38589) **Properties and shorthands** - Print align-items:center without a stray space when no safe/unsafe keyword is given (#41993). 3,317 real stylesheets - Emit the physical longhands instead of the inset shorthand for targets without it (#38583). 1,452 real stylesheets - Keep the stops of an upward gradient as written, and drop a `50%` hint only at the midpoint (#46790). 104 real stylesheets - Emit unparsed border-block-* declarations when compiling logical borders (#38582). 89 real stylesheets - Keep repeated font families and dedupe only the inserted system-ui fallbacks (#46662). 88 real stylesheets - A `width` / `height` / `min-*` / `max-*` with `var()` or `env()` was printed before the plain fallback written above it, so the fallback won (#42101). 26 real stylesheets - Keep box-orient and box-direction when flex-direction or flex-flow follows (#45672). 16 real stylesheets - Write held prefixed background declarations at every flush (#46882). 6 real stylesheets - Derive equality for Size2D and BorderRadius, and keep every prefix in the border-radius handler (#45665). 2 real stylesheets - Print `none` instead of an empty border-image, mask-border or mask-box-image value (#45143). 2 real stylesheets - Keep font/transition sub-properties on the side of the shorthand they were written on (#41990). 2 real stylesheets - CSS-wide keywords are not names: `font:12px Arial;font-family:inherit` printed `font:12px inherit`, `color-scheme:inherit` and `color-scheme:auto` printed `normal`, `transition-property:unset` was folded into `transition` (#42022). 2 real stylesheets - Only fold font longhands into `font` when the rule declared a `font` (#45459) - Keep a font family name quoted when its identifiers do not read back as the same name (#46606) - Stop rewriting valid positions into ones browsers reject (#45197) - `border` is no longer built from longhands unless the rule also sets what `border` resets (`border-image`), and an author's `border-image` reset is no longer dropped. `transition` is likewise only written where the rule wrote one, because it resets `transition-behavior` (#42072) - `border; border-image: <gradient>; border-image-slice: 1` lost the gradient in every default build (#42018) - A prefixed `linear-gradient` keeps its direction, written or generated: the prefixed syntax names the starting side and measures angles differently (#46697) **At-rules** - Print @font-face format() keywords as strings (#37979). 439 real stylesheets - Print @supports `not` conditions without a leading space (#38559). 88 real stylesheets - Reset after the number token of a unicode-range (#45835). 33 real stylesheets - Keep `<general-enclosed>` media and container conditions as written (#46756). 24 real stylesheets - A strict range such as `(width < 768px)` lowered for old targets still matched at exactly 768px. The step is now `.02px`. The `not all and` form for other units is not taken (#46806). 18 real stylesheets - Keep scanning an @supports condition after a nested block (#38552). 9 real stylesheets - Every `@counter-style name` printed as `@counter-stylename`, which browsers drop (also #46692). In a CSS module the name now stays global, like the `list-style` that refers to it (#33679). 9 real stylesheets - Keep a keyframe whose block has an invalid item (#46288). 2 real stylesheets - Read an @Property initial-value on the stylesheet's parser, keep an unmatched value as written (#45806). 2 real stylesheets - `@media {}` is `all`. A media query that stops after `and`, `or` or `not` (`@media screen and {`) is a build error; `main` printed `not all` or dropped the condition, silently. The `@layer` and type selector parts are not taken (#46869). 2 real stylesheets - Accept a name-only `@container` and a `style()` feature with no value (#46689). 1 real stylesheets - Parse `<timeline-range-name> <percentage>` keyframe selectors (#45652) - Allow `or` inside parentheses after a media type (#45088) - Print the `=` comparison in media and container queries as `=` (#45071) - Parse the @font-palette-values font-family descriptor as a list of family names (#45484) **Selectors** - Never wrap a selector list in :is() (#46787). 414 real stylesheets - Stop emitting :-webkit-any() copies of :is() that outrank the original rule (#42029). 373 real stylesheets - With browser targets, a selector list with a vendor-prefixed member was split, which revives hacks that rely on other engines dropping the whole list: `.s *::-ms-backdrop,.s{flex:auto}` applied everywhere. Rewritten; the list is printed as written (#42100). 42 real stylesheets - Print the vendor prefix on downleveled :any-link, :read-only, :read-write, :placeholder-shown and :autofill (#42131). 12 real stylesheets - Fix nesting lowering of a `&` that does not lead its selector (#43047). 8 real stylesheets - `@scope`: `&` and implicit selectors compile to `:where(:scope)`, relative selectors and bare declarations parse (#43165). 7 real stylesheets - Only reject bare :global / :local pseudo-classes in CSS modules (#38534). 5 real stylesheets - Stop truncating `@scope to (...)` and stop replacing `&` in the scope-end selector (#43146). 2 real stylesheets - `[xl|href$=".pdf"]` lost its namespace prefix (#45159). 2 real stylesheets - Match An+B keywords exactly and take only `+` as the leading sign (#42953). 1 real stylesheets - Parse ::details-content and ::picker() like ::part() (#45504). 1 real stylesheets - Parse :window-inactive as an ordinary pseudo-class, and accept it after ::selection (#45815) - Print :nth-col(1) and :nth-last-col(1) in functional form (#41575) - `li::before::marker` failed the build (#45810) - `&` inside `:nth-child(... of S)` is resolved when nesting is compiled away. The second selector serializer (326 lines) is deleted (#43024) **Colors and `Bun.color`** - Keep light-dark() as written under the default browser targets (#42009). 227 real stylesheets - Number and percentage channels parse in `lab()`, `lch()`, `oklab()`, `oklch()`, `hsl()` and `hwb()`; the hue of `lch` / `oklch` is no longer scaled by alpha (#45084). 130 real stylesheets - `Bun.color` returns `null` for `currentColor`, system colors and `light-dark()` in the converting formats, instead of the CSS keyword as a string (#33047). 130 real stylesheets - Relative colors: channel keywords are on the scale of their function (`rgb(from #369 calc(r + 10) g b)`), the origin's alpha is kept, a relative color kept as written gets no `@supports` copies, and a result outside sRGB is not folded (#45362). 31 real stylesheets - Keep rotate: 0deg out of none, and keep the origin alpha in relative colors (#38486). 13 real stylesheets - Compute the D50 reference white in f32 so greys convert to lab(l 0 0) like lightningcss (#38535). 7 real stylesheets - Return a missing hue for a grey from conversions into lch, oklch, hsl and hwb (#45201). 5 real stylesheets - Fix color(a98-rgb), srgb-linear relative colors and color-mix(in xyz-d50) (#38487). 4 real stylesheets - Match named colors without regard to ASCII case (#45092). 3 real stylesheets - Fold min(), max() and clamp() over plain numbers (#39515) - `calc(l - .08)` in a percentage channel of a relative color became NaN and printed `#000` (also #45970) (#45971) - Bun.color: convert color() inputs instead of returning them as a CSS string (#38488) - A `color-mix(in srgb, ...)` result outside sRGB prints `color(srgb ...)` instead of a gamut-mapped hex (#39269) **`calc()` and numbers** - Rounding to 6 significant digits ate into the integer part: `z-index:2147483647` became `2147480000`, `max-width:9999999px` became `10000000px`, `--x:1234567.5` became `1234570`. It now only cuts a fraction short: a value kept as tokens prints its source text, a typed value prints every integer digit and at least one digit of the fraction (#46715). 43 real stylesheets - A number without a unit is no longer repaired into `px` (`height:1.5715` is dropped by a standards-mode browser, so it prints as written), `calc(-1 * 0)` is not a length, and on a property of the range [0,∞] (sizes, border radii, padding, border and outline widths, gap, `flex-basis`, `font-size`) a `calc()` that folds below zero prints `0` instead of an invalid negative literal, and a negative literal no longer replaces the valid declaration before it (`width:10px;width:-5px` printed `width:-5px`) (#42104). 24 real stylesheets - Print numbers from the f32's shortest digits, not its f64 expansion (#38565). 17 real stylesheets - Print negative numbers below 1 with a single minus sign (#38516) - Keep math functions over two different length units as written (#38489) - Fold rem() with a truncated quotient, so it keeps the sign of the dividend (#32286) - A one-argument `min()` / `max()` around a sum printed without any function (`width:100% - 20px`) (#46145) - `round()` breaks ties upward and handles a negative step as browsers do (#45249) **CSS modules** - A CSS module exports its `@keyframes` names (`styles.spin`). Hashing is unchanged (#46720). 145 real stylesheets - A name inside `:global(...)` prints plain but was exported as `name_<hash>`, a class no rule has (also #38573) (#45487). 90 real stylesheets - Keep container names global in CSS modules (#45247). 6 real stylesheets - Tag the keyframes name when an `animation` value falls back to raw tokens (#46034). 6 real stylesheets - In a plain stylesheet `composes: a from "./b.css"` was treated as an import: the file was inlined and an absolute path printed (#45961). 4 real stylesheets - Drop a rejected composes instead of failing the file at print time (#38538). 1 real stylesheets - Keep every rule's custom properties for the composes conflict check (#38523) - Keep composes working after a nested rule in the same block (#38520) - `IdentOrRef::hash` read 2 of 16 bytes, so in release builds every class of a module hashed alike (#30784) **Tokens, `url()`, diagnostics** - The block skip stack no longer allocates on every block exit (#39533) - Report the diagnostic's line without its line breaks in position.lineText (#38342). 192 real stylesheets - Compare `url()` values by their text (#46895). 26 real stylesheets - Values kept as tokens keep the blanks they were written with instead of having them re-invented at print time: `attr(x type(<number>))` printed `type(< number> )`, which browsers drop. Minified output still drops the blanks that cannot matter (#45577). 19 real stylesheets - The IE star hack (`*zoom:1`) failed the whole build. The declaration is skipped, as every browser does. It is the one syntax error that builds: tachyons, handsontable and jasmine ship it (#46751). 8 real stylesheets - The path of a copied asset spliced into `url()` is always quoted, so a file name with a space or a parenthesis cannot end the `url()` (#41557). 7 real stylesheets - Move the skip loop of parse_until_before out of the generic body (#39520) - Remove dead code from bun_css: the unused `impl Default for Property` (#45618) - Default the at-rule and qualified-rule parser traits, drop the url_to_css shim (#31999) **Speed** Four inputs that took quadratic or exponential time, or produced output out of proportion, are now linear, with no new limit and no extra pass (#31639, #42243, #38531, #43421). **Tests only** - `css-fuzz.test.ts` never ran in CI and timed out on debug builds; it is a deterministic table now (#38500) - `nth-anplusb-ident.test.ts` counts heaps in a child process (#46331) - `color.test.ts` checks the ansi-16 sweep with one `expect()` (#42824) - Not CSS, but it failed this PR's CI and fails on `main` too: `ws-proxy.test.ts` on Windows, "a message sent during a TLS renegotiation arrives after it". The helper server now renegotiates from the callback of the frame's write (#46170) **No pull request covered these** - `--v: 5.0.1` printed as `5.1`, `--w: 1.0.0` as `10`, `--x: 1+2` as `12`, `2n+1` as `2n1`: a number token that touches another keeps its source text. - `color-scheme: auto` printed as `normal`, and `color-scheme: dark light` as `light dark`. - A bare `:global` or `:local` in a CSS module sets the scope of the names after it, up to the end of the selector, as in css-loader. It was a build error. - The scrollbar states (`a:horizontal`, `::-webkit-scrollbar{&:horizontal{}}`) are valid in a plain compound, as in WebKit and Blink. - Without browser targets, `-webkit-box-align`, `-ms-flex-align` and the like were dropped next to their standard form (flatpickr, foundation-sites, materialize-css: 28 stylesheets), and `-webkit-fill-available` before `-moz-available` (beercss). - `(-o-min-device-pixel-ratio: 2/1)` printed as `2`. - `sin()`, `cos()` and `tan()` are exact at multiples of 90deg: `calc(100px * cos(90deg))` printed `-.00000437114px`. - A `display-p3` color at targets that have P3 but not the other `color()` spaces (Safari 10.1 to 14) got itself as a fallback. - `width: rem(-18px, 5px)` folds to a negative literal once `rem()` is right; it prints `0`. - Consecutive nested declarations rules, which arise when same-query `@media` blocks in one rule merge, are folded into one and count against the existing selector expansion limit as the `&{}` rules they replace did. #### Known and not fixed here - Four longhands are still folded into a `transition` the author did not write where the targets add a prefixed copy of a property (`mask-image` at Chrome 80): only the shorthand gives the copy its own times. - A later `background`, `box-shadow` or `border-*` declaration still loses to the `@supports` copy of an earlier `var()` value of the same property with a wide-gamut color. Same on `main`; #45560 is taken for the properties of the fallback handler and for unparsed values only. - A merged rule prints the unprefixed name in the passes of the rule it absorbed: `.d::-webkit-input-placeholder{}.d::-moz-placeholder{}` prints `::placeholder` for the second (#42106, not taken: it breaks the merge of prefix-equivalent rules). - The `border`, `outline` and `font` shorthands, `line-height`, `scroll-padding`, `background-size` and a few more still print a `calc()` that folds below zero as a negative literal. No real stylesheet has one. - `all` is not a property Bun knows, so `a{margin-top:1px;all:unset}` prints `all` first. Same on `main`. - A selector kept as raw tokens loses the blank before `*` when minified: `--sel: .dark *` prints `.dark*`. Same on `main`. - `width:calc(0% + 12px)` folds to `12px`, which lays out differently in a table cell. Same on `main`. - The `:dir()` / `:lang()` rules of a lowered logical property print before the nested rules of their rule, so a logical declaration written after a nested rule of equal specificity still loses to it. Same on `main`. - A fraction is still rounded to 6 significant digits (`12345.678` prints `12345.7`, `33.3333333333%` prints `33.3333%`). Keeping every digit would add up to 282 KB over the corpus. - `@keyframes "quoted"` is hashed in a module but not exported. - In a module, a keyframes name inside a `var()` fallback is not hashed: `animation: var(--enter, fade 1s)`. Same on `main`. - A `color-mix()` or relative color folded to a hex inside a gradient changes the interpolation from Oklab to sRGB (VS Code, clawhub). Printing `color(srgb ..)` instead needs a fallback for `mask-image`, `list-style-image` and custom properties at the default targets, which have none. - A comma list in `@container` still fails the build. - After a bare `:global`, names that are hashed at print time (`::view-transition-old(foo)`) are still hashed; inside `:global(...)` they are not. #### Pull requests in scope that do not land here - Duplicates of a pull request that lands here: #36961 (of #37979), #38478 (of #46662), #38480 (of #46733), #38482 (of #46715), #38491 (of #38500), #38508 (of #45201), #38513 (of #45362), #38573 (of #45487), #38640 (of #38500), #45525 (of #45247), #45589 (of #46756), #45970 (of #45971) - Already fixed on `main`: #38674 - Right, but for input nobody writes (0 of 10,116 stylesheets, and not new syntax): #31916, #38526, #38592, #39349, #41139, #41801, #42042, #42484, #43078, #45604, #45908, #46086, #46221, #46224, #46273, #46694, #46707, #46737, #46755, #46816, #46870, #46934 - Right or harmless, but not worth their code, their bigger output or the behavior they change: #30905, #31924, #33332, #34426, #36225, #38006, #38512, #38547, #38551, #38561, #38572, #38576, #38607, #38623, #38667, #38692, #42106, #42912, #42918, #43407, #43434, #44700, #45442, #45546, #45747, #45759, #45825, #45946, #46061, #46127, #46206 - Need a decision (see above), stay open: #40368, #40369, #44647, #44648, #45814 - Stays open: #45787 Out of scope: CSS linking and chunking in the bundler, the dev server, docs-only pull requests, and repository-wide sweeps that touch `src/css` in passing. Thanks to @mikamikasuki (#45247), @alii (#39520, #31999) and @oddharsh, whose measurements on #40369 and #41990 were used. Fixes #16727. Fixes #24770. Fixes #30772. Fixes #44704. Fixes #45089. Fixes #45237. Fixes #46872. ### How did you verify your code works? - The 35 CSS test files pass on a debug build, also with `FORCE_COLOR=1`. 600+ of the tests in this branch fail on a build of `main`. An earlier head of this branch passed all 179 CI jobs that ran. - The reproduction of each issue listed above was run on `main` (wrong) and on this branch (right). - Differential run over the 10,116 stylesheets, `main` against this branch, minified without targets and through `Bun.build` at the default targets: no stylesheet that builds on `main` fails; Chromium 156 compares the output with the input rule by rule (CSSOM, then computed values on a sized element in a standards-mode document, colors as painted pixels in sRGB and P3). The comparison has 195 control pairs that must read equal or different. For stylesheets that read differently on both builds, mostly because of lowering, the sets of differences were compared; the three new ones are two minifier fixtures that are wrong on both and one comparison artifact. - CSS modules are checked for consistency instead, since hashed names defeat the comparison: every reference points at a name the output defines, every export exists. - `Bun.color`: 59 inputs in 13 formats on both builds; every changed cell was read.

Jarred-Sumner · 2026-10-27T19:53:58Z

Landed in #47025 (7942008).

The :-moz-any() copy of every rule with :is() or :not(a, b) is gone: Firefox 78 has :is(). 1,164 real stylesheets

robobun · 2026-10-27T20:57:41Z

Thanks. I ran a debug build of main at 7942008 to record which part of this PR #47025 has.

On main:

The default targets print no :-moz-any() copy. a:is(.b,.c){color:red} prints the :-webkit-any() rule and the :is() rule. The range ends at Firefox 77 (src/css/prefixes.rs:2159), and the generator skips the firefox_android record (src/css/build-prefixes.js:61).
test/bundler/css/is-selector-21169.test.ts, test/regression/issue/25794.test.ts and the two :is() cases in test/js/bun/css/css.test.ts pass.

Not on main:

The regeneration of the table (commit 930cfff). width: stretch still loses -moz-available at Firefox 133, and -webkit-fill-available at Safari 18.1 and at Chrome 131 (src/css/prefixes.rs:1253-1294).
No public option sets such a target, so no build shows this today. It starts to show when a target option such as Bun.build: add cssTarget option to set CSS browser targets #40368 lands.

The range-rule follow-up that the PR body asks about has no pull request. Its code is on the branch robobun/9f0abb7d/css-prefix-range-rule.

robobun added 2 commits October 18, 2026 15:02

github-actions Bot added the claude label Oct 18, 2026

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css: check the generated enums before the prefix generator writes a file

2ee5ae5

A run with no argument wrote targets.rs and prefixes.rs and then stopped at the check for compat.rs. Both checks now run before the first write, so a run that fails changes no file.

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Jarred-Sumner mentioned this pull request Oct 27, 2026

css: consolidate the open CSS parser fixes #47025

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css: stop printing the `:-moz-any()` copy for Firefox 78, and regenerate the vendor prefix table from one caniuse-lite copy - #45945

css: stop printing the `:-moz-any()` copy for Firefox 78, and regenerate the vendor prefix table from one caniuse-lite copy#45945
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