Change Log

9.9.0

Minor Changes

  • cssnano now ships its presets and plugins in a single package, so installing it adds one cssnano package to your dependency tree instead of about thirty, and you have fewer packages to review in audits and lockfile updates.

    preset: 'lite' and preset: 'advanced' now work without installing another package. An installed preset package still takes precedence over the built-in one and prints a one-time CSSNANO_INSTALLED_PRESET warning; pass the imported preset function to keep it without the warning. Full names such as cssnano-preset-default fall back to the built-in preset when no package is installed. Projects that require cssnano-preset-default directly must declare it as a dependency, or switch to preset: ['default', {...}]. overrides and resolutions that pin an individual plugin no longer apply.

9.8.0

Minor Changes

  • feat(postcss-normalize-url): stop rewriting URLs

    The plugin only changes the url() token (unquoting, whitespace, escaping) and keeps the URL byte-identical. It no longer removes dot segments or duplicate slashes, decodes percent-escapes, removes default ports or strips the trailing dot of host names, because these are not equivalent for every server or bundler. It keeps whitespace inside a quoted @namespace URL as well, because the namespace name is an identifier compared character by character rather than a URL that gets fetched.

  • feat(cssnano-preset-default): remove postcss-svgo from the preset

    The presets no longer run postcss-svgo; run it before cssnano or optimize SVG assets with the SVGO cli instead. A svgo option is now ignored. The output changes for CSS with inline SVG data URIs, and for CSS with URLs that postcss-normalize-url used to rewrite (see the postcss-normalize-url changeset).

Patch Changes

  • Always convert between cm and mm, and convert q to cm or mm, since metric units relate by exact decimal factors. q is never the output unit.

9.7.0

Minor Changes

  • feat(postcss-minify-params): drop a min-* or max-* already implied in another range in the same media query

Patch Changes

  • fix(postcss-merge-rules): merge at-rules separated by unrelated rules

9.6.0

Minor Changes

  • feat(postcss-merge-longhand): merge row-gap/column-gap, overscroll-behavior-x/-y, flex-direction/flex-wrap, column-rule-* and equal overflow-x/-y into their shorthands when every target supports them

Patch Changes

  • refactor: remove cssesc dependency

  • fix: improve escape handling in selectors

  • fix: update postcss-calc

  • fix(postcss-minify-selectors): match escaped pseudo-class and pseudo-element names ASCII-case-insensitively, so U+212A KELVIN SIGN no longer folds to k. This covers escaped pseudo names, :nth-* keywords such as of, odd and even, from in keyframe selectors, and url() in namespace rules

  • fix: accept the optional leading rounding strategy of round(), such as round(up, 1s, 1s), when postcss-ordered-values orders animations and transitions and when postcss-merge-longhand folds shorthands. The rounding strategy must be separated by a comma, so round(up 1px, 2px) is no longer treated as valid. postcss-merge-longhand no longer folds math functions with missing operators, such as calc(1px 2px). postcss-merge-longhand, postcss-ordered-values and postcss-merge-rules now compare property names, keywords and units ASCII-case-insensitively.

9.5.0

Minor Changes

  • feat(postcss-normalize-unicode): merge adjacent, overlapping, and out-of-order unicode-range entries, and emit a wildcard range when they cover a range expressible with trailing ? wildcards

Patch Changes

  • fix(postcss-normalize-whitespace): trim and collapse spaces and tabs between the names of each string row in grid-template-areas, grid-template and grid.

9.4.0

Minor Changes

  • feat(cssnano-preset-default): run postcss-merge-longhand again after postcss-merge-rules, so declarations overridden in a later rule with the same selector are discarded

  • feat(postcss-merge-longhand): merge flow-relative and physical box properties safely

    The plugin now merges and shortens margin-block, margin-inline, their padding, inset, scroll-margin and scroll-padding counterparts, and the physical inset, scroll-margin and scroll-padding longhands. It never assumes a writing mode or direction, so a flow-relative declaration moves only where no physical declaration of the same group. It creates a shorthand only when every browserslist target supports it.

  • feat(postcss-merge-longhand): discard overridden same-property declarations

    Within a rule, a declaration is dropped when a later declaration of the same property and the same !important overrides it, and every browser that accepts the earlier value accepts the later one.

Patch Changes

  • fix: update postcss to 8.5.29

  • fix(postcss-merge-longhand): keep fallbacks for older browsers in more cases. Longhands that use calc() merge into a shorthand only when every target parses calc(), which Opera Mini, and so the default targets, do not. When a browserslist target predates the support floor (such as IE 8 or Opera 12), the plugin keeps fallbacks for rem, angle and time units and hsl(), so font-size:16px before font-size:1rem survives.

  • fix: update color processing library

  • fix(postcss-merge-longhand): add missing tokenizer runtime dependency

9.3.2

Patch Changes

  • Leave animation untouched when the keyframes name is a keyword another longhand would claim, such as animation: ease 1s linear. Reordering the name first made browsers read it as the timing function, direction, fill mode or play state.

  • Omit trailing zero blur radius and spread distance in box-shadow, e.g. 0 50px 0 0 #fff becomes 0 50px #fff.

  • Merge column-width and column-count into columns when the width is zero, for example column-width:0px;column-count:2 becomes columns:0px 2. CSS Sizing 4 allows a zero column-width; a zero column-count stays invalid and is left untouched.

  • Share declarations among several adjacent rules also if the file size can be reduced by merging more than two rules. Previously rules were only merged when the first merge immediately yielded a saving, without checking if further merging was possible.

9.3.1

Patch Changes

  • feat(cssnano-utils): add sameContainer export

9.3.0

Minor Changes

  • Merge rules with the same selector and sibling @media, @supports and @container blocks with identical conditions even when other rules sit between them, when none of those rules sets a conflicting property.Do not merge rules across all, shorthands that reset their longhands, logical properties that can address the same side, and at-rules whose order matters, such as @layer and @import. Adjacent rules with the same selector now become one rule. Add the selectors of a later rule to an earlier rule with the identical declaration.

Patch Changes

  • Keep an empty @layer block when it may fix the layer order. Decode CSS escapes before comparing @layer names.

  • Remove the enclosing named @layer and conditional blocks that moving a rule out of a nested conditional group rule left empty.

  • Do not merge nested rules when a conflicting declaration from the enclosing rule lies between them, so .p{&{color:red}color:blue;&{color:red}} stays red instead of blue.

  • Determine the vendor prefix of a selector only from its pseudo-class and pseudo-element names. A class name or attribute value such as .x-moz-y or [title=":-moz-x"] no longer blocks merging with a ::-moz-selection rule, and a selector that mixes two vendor prefixes is never merged. Compare pseudo-element names case-insensitively, so ::-WEBKIT-scrollbar now counts as WebKit-prefixed and stays apart from unprefixed rules.

9.2.2

Patch Changes

  • Fix an infinite loop: when equal @media blocks were separated by an at-rule such as @layer x;, @font-face or @page, the plugin would keep merging a rule into itself until memory ran out.

    Fix a bug when the plugin moved a rule into a block nested inside another block: a later merge could combine two rules in reverse order and change which declaration wins.

9.2.1

Patch Changes

  • Remove a declaration that a later sibling @media, @supports, @container or named @layer block with identical conditions repeats, so duplicates are dropped before postcss-merge-rules joins the blocks.

    Keep an earlier duplicate @media, @supports or @container block that declares an @layer, so removing it no longer moves the layer’s first appearance and changes the layer order. Also keep a rule that holds a /*! comment when its declarations are removed.

    Keep a duplicate @import, so removing the earlier copy no longer changes the layer order.

  • Keep "revert-rule" quoted in font-family because revert-rule is a CSS-wide keyword.

  • Recognise revert-rule as a CSS-wide keyword. postcss-ordered-values no longer reorders a border, animation, transition, list-style, box-shadow or grid-row value as if revert-rule were a color, name or type. The reserved keywords are now generated from @webref/css.

9.2.0

Minor Changes

  • Merge box alignment properties into the place-content, place-items and place-self shorthands, such as align-items:center;justify-items:start into place-items:center start. This only happens when every browser in your Browserslist targets supports the shorthands, because a browser that does not would ignore both alignments. The defaults query includes browsers with unknown support, such as Opera Mini and UC Browser, so it keeps the longhands. Values that use safe, unsafe or last baseline merge only when both values use the same keywords. postcss-merge-longhand now accepts the Browserslist options overrideBrowserslist, stats, path and env.

Patch Changes

  • Write numbers in scientific notation when it is shorter, such as 1e-6px for 0.000001px and 1e6px for 1000000px. This also applies when length unit conversion is disabled. Numbers written without a decimal point, such as z-index:1000000, keep their form, because an <integer> cannot use scientific notation.

  • Stop merging longhands across a nested rule or at-rule. The shorthand ended up after the nested rule and overrode it, so in a{margin-top:1px;&{margin-top:2px}…} the nested margin-top was lost. This applies to margin, padding, border, border-radius and columns. Declarations on each side of a nested rule are now merged separately. An at-rule without a block, such as @apply x;, also separates them, since it may add declarations. An empty rule such as &{} does not. A border-image or all declaration before a nested rule no longer prevents merging the border longhands after it.

  • Stop merging rules that have an invalid selector, such as b: hover, [a b], :lang(en fr) or a||b. An invalid selector makes the whole selector list invalid, so the browser also dropped the valid rule it was merged with.

  • Only treat a dimension as the font size in the font shorthand when it has a length unit. An invalid value such as font:bold 1s "Arial Black" is now left unchanged.

  • Leave the font shorthand unchanged when it contains attr(), if(), inherit() or a custom function such as --name(), as already done for var() and env(). Their result is only known when the browser computes the value.

  • Remove a zero color stop position only when it has the right type for the gradient. conic-gradient() now drops 0deg and keeps an invalid 0px, while linear and radial gradients still drop 0px. -webkit-linear-gradient() keeps to bottom and other to directions as written, since the prefixed syntax measures angles differently.

  • Stop turning a comment inside a selector into a descendant combinator. A comment is not whitespace, so .a/**/.b selects elements with both classes, including inside :is(), and is no longer rewritten as .a .b. Invalid selectors such as div/**/span are left as written instead of becoming valid.

  • Leave rules with an invalid selector unchanged, including an ID selector that starts with a digit, such as #1a, and a combinator after a pseudo-element, such as a::before b.

  • Shorten top center and bottom center to top and bottom, instead of 0 and 100%, which the browser reads as horizontal positions. center top and center bottom are now shortened the same way.

    Leave a position unchanged when it cannot be safely rewritten:

    • in a background layer where another value splits the position, as in left no-repeat center, which is invalid;
    • when it contains a function such as attr(), if() or a custom --function(), which may return a keyword, as var() already did;
    • when an invalid three-value position contains a math function, such as left abs(1px) top, as calc() already did.

  • Keep strings unchanged when removing a line continuation (a backslash before a newline) right after an escape. In "\31 followed by a line continuation and 2", joining the lines would turn \31 into \312, so the result is now "\31 2".

    Leave @charset unchanged. Browsers only recognize it with double quotes, so rewriting single quotes would make an ignored @charset take effect.

  • Update postcss-calc to 11.2.2. Multiplications inside calc() now keep their original operand order, so calc(var(--x) * 5) is no longer rewritten as calc(5 * var(--x)).

9.1.2

Patch Changes

  • Omit redundant whitespace after @media and @supports when parameters begin with parentheses, and normalize multi-character whitespace after at-rule keywords.

  • fix: update browserslist

9.1.1

Patch Changes

  • Preserves Unicode range tokens (unicode-range) in font descriptors and custom properties, preventing code point ranges from being corrupted into invalid numbers or dimensions.

9.1.0

Minor Changes

  • Merge corner border-*-radius longhands into border-radius shorthands. Four complete corner declarations in the same importance lane now collapse into one shorthand, with horizontal and vertical axes minified independently and separated by a slash when distinct. Declarations in the radius family are decoupled from physical border fast-path eligibility, allowing rules containing both physical borders and border radii to optimize both families.

Patch Changes

  • Merge margin, padding, border, border-radius, columns, and border-spacing declarations inside at-rule containers such as @page, @position-try, and nested at-rules. Fold identical horizontal and vertical border-spacing components to a single value. Recognize columns shorthands combining a count and a math function in either order, and preserve invalid declarations as written: border shorthands with multiple styles and columns values combining CSS-wide keywords with widths or counts no longer discard preceding valid longhands.

  • Preserves percentage units in registered custom-property initial values with composite syntax, ranges, groups, and multipliers, and avoids clamping numeric operands nested inside alpha-value functions.

  • Restricts color minification to CSS properties that accept <color> and custom properties, preserving custom identifiers in properties like animation-name, grid-area, and counter-reset. Adds support for hwb() color values and minification inside color-mix(), light-dark(), and var() fallbacks, while preserving relative color syntax, math functions, and token boundary separators.

  • Preserves zero percentage units in rgb(), rgba(), and modern CSS Color 4 functions to avoid invalid syntax, respects disabled time conversions for 0ms, clamps percentage opacity values adhering to CSS Color 4 alpha semantics, and improves compatibility with uppercase at-rules and vendor-prefixed keyframes.

  • Preserves zero length in columns shorthands and zero units inside @property with <angle-percentage> syntax, retaining keyframe percentage units under nested rules. Symmetrically rounds negative numbers when precision is configured, converts between metric units (mm, cm, q), preserves zero percentages on SVG stroke properties to retain transition interpolation, and caches Browserslist lookups across runs. Also preserves units inside CSS Fonts 5 override descriptors, anchor() functions, flex-basis, and IE-targeted sizing properties.

  • Remove comments more reliably and preserve the ones you keep exactly. Comments are now removed from declaration values that carry !important, and comment detection respects CSS token boundaries: text inside unquoted url() values and behind escape sequences in strings and identifiers is no longer mistaken for a comment. Kept comments are emitted byte-for-byte, including an unclosed comment at the end of a value, and whitespace inside kept comments is left untouched. Removal state is scoped to each document, so a shared processor no longer carries removeAllButFirst first-comment state between runs, and the remove callback runs once per comment occurrence. A non-function remove option now fails with a TypeError.

  • Adds the balanced token index used by selector, parameter, and gradient minification while preserving their serialized CSS output.

  • Improve conformance for modern CSS math functions, grid-line values, and case-sensitive attribute selector modifiers while preserving ambiguous or invalid declarations. The affected transforms now use bounded, linear scans for these forms.

  • Value transforms now read the CSS Values 4 math function names from one mathFunctions table in cssnano-utils, so unit retention, box and shorthand merging, parameter and whitespace handling, and time classification agree on which functions count as math functions. Serialized output is unchanged.

  • Standardize output normalization for margin, padding, and physical border properties. Property names and case-insensitive keywords in generated shorthands and normalized standalone shorthand declarations are canonicalized to lowercase, while preserving author casing for unmerged longhands, custom properties, hack prefixes, and unresolved values.

  • perf: median 15% speed increase on test fixtures

  • postcss-normalize-url now decodes quoted url(...) values, preserving literal backslashes and escape sequences whether quotes are stripped or kept. Relative URLs now normalize using POSIX path semantics across all platforms, and converted @namespace URLs escape double quotes.

  • Join every escaped line continuation in a multiline url() value into one line, including \r\n continuations that previously survived and left an invalid string behind. Rewriting a @namespace URL no longer overwrites the tokens that follow it, so trailing text is preserved and multiple URLs in one namespace declaration are each normalized.

  • Remove insignificant whitespace around custom-property names and, in standard declarations, around env() custom-ident arguments and around comma delimiters in var(), env(), and constant(). Between a custom-property name and its value, only the parser-consumed leading whitespace run is dropped; authored whitespace elsewhere in the value, such as after a preserved comment, is preserved per CSS Variables 1. Required whitespace between distinct tokens and the single whitespace token in an empty fallback remain preserved, and a preserved comment kept between a declaration name and value now survives minification, for custom properties and standard declarations alike. Comment removal in selectors and values no longer fuses the tokens the comment sat between: an attribute case-insensitivity flag or any other name-like token keeps its boundary, and math-operator spacing is restored for every function whose value productions accept <calc-sum> arguments (including calc-size(), calc-mix(), and random()). Values without comments are now left byte-for-byte untouched rather than re-spaced.

  • Preserve whitespace around division operators across all modern CSS math functions such as min(), max(), and clamp(), and ensure commas in nested calculations have extraneous whitespace trimmed.

  • Orders columns: 2 auto as columns: auto 2. Leaves animation declarations with negative iteration counts unchanged. Reorders border and box-shadow math functions that resolve to a length, such as calc(1px + 1em), and leaves other math unchanged. Passes through unknown box-shadow color functions instead of reordering them.

  • Merge duplicate @keyframes and @counter-style definitions more conservatively.

  • Use ASCII case-insensitive matching for CSS names and grammar keywords so Unicode lookalikes are preserved, and restrict CSS whitespace normalization to the CSS whitespace set.

  • Rename identifiers only when their definition and a reference share a stylesheet; leave alone names inside var(), env(), attr(), or a custom property fallback; skip reserved words in the encoder; rename reversed() counters and implicit <area>-start/-end lines with their area.

  • Preserve Windows drive roots, directory dot references, and leading ./ prefixes when the first relative segment contains a colon. Decode unreserved percent-encoded octets while preserving percent-encoded dots, normalize @import at-rules including nested condition URLs, retain quotes for URLs containing non-printable control characters, avoid unnecessary declaration tokenization, and synchronize raw parameters.

  • Minify equal shorthand components for two-axis, four-side, alignment, aspect-ratio, and transition declarations while preserving grammar-sensitive and invalid values.

  • fix(postcss-minify-params): support CSS values level 4 and Media Queries level 5

  • Preserves invalid selector syntax and namespace-sensitive universal selectors while safely normalizing pseudo-element, View Transition, and keyframe forms. Recognizes the full token grammar for An+B formulas, including escaped forms and exact large integers.

  • fix(postcss-ordered-values): improve performance and correctness

  • Aligns SVG data URI processing with WHATWG URL standards by treating the first # as the fragment delimiter. Non-conforming data URLs (such as those with malformed percent-encoding or where an unencoded # in markup truncates the SVG payload) are left untouched rather than parsed with an internal XML recovery scanner. CSS hex escapes in the URI scheme (for example d\61ta:image/svg+xml) reach the optimizer. SVG data URIs inside CSS Values 4 src(...) functions or url(...) declarations with url-modifiers are optimized while preserving modifiers and comments. Minified declarations also keep their raw value metadata in sync.

  • Unify physical-border optimization under a single reducer that chooses deterministic shortest non-crossing canonical shorthands from complete side and component groups, partitioned by importance lane. Partial grids no longer require a full border reset. Dynamic declarations, style hacks, CSS-wide keywords, support fallbacks, unresolved substitutions, and other cascade barriers remain in their original positions, while valid fallback and border-image behavior is preserved.

  • Parse font weights and column units from tokenizer metadata. This safely minifies escaped bold weights, recognizes escaped length units, and prevents partial rewrites of invalid font shorthands while preserving original source spelling.

  • update browserslist

  • Preserve matching-importance all reset boundaries when merging margin, padding, physical border-radius, and columns declarations, so minification does not restore values cleared by the reset.

9.0.5

Patch Changes

  • fix: updae browserslist, mdn-data, autoprefixer

  • fix(postcss-svgo): better decode encoded SVG

  • fix: update postcss-calc

  • fix: update calc and color minifiers, autoprefixer

9.0.4

Patch Changes

  • fix(cssnano-preset-default): update postcss-calc

9.0.3

Patch Changes

  • fix(postcss-colormin, postcss-minify-gradients): update color parsing library

  • fix: update postcss and selector parser

  • fix: update conflict detection and color conversion CSS spec conformance

  • fix: update PostCSS peer dependency

9.0.2

Patch Changes

  • fix: ensure older tools can resolve cssnano packages

9.0.1

Patch Changes

  • perf(postcss-minify-selectors): avoid quadratic selector scanning

  • pef(stylehacks): avoid rescanning the nodes when checking for compatibility hacks

9.0.0

Major Changes

  • breaking: do not load configuration from package.json

  • cssnano now discovers configuration only in the current working directory, using .cssnanorc.json or cssnano.config.js in that order.

  • The cssnano packages are now native ESM and require Node ^22.22.3 || ^24.15.0 || >=26.0. Package subpath imports are no longer supported. See the migration documentation before upgrading.

  • fix!(cssnano): introduce new postcss-calc plugin

Patch Changes

  • Updated dependencies:
    • cssnano-preset-default@9.0.0

8.0.10

Patch Changes

  • fix(postcss-normalize-charset): ensure idempotent charset normalization

8.0.9

Patch Changes

  • fix: update svg and color processors

8.0.8

Patch Changes

  • fix(postcss-minify-gradients): follow CSS specification more closely when minifying gradients

8.0.7

Patch Changes

  • fix(postcss-ordered-values): recognise easing functions

  • fix(postcss-reduce-initial): update MDN data

  • fix(cssnano): tighten option types

  • perf(postcss-merge-rules): cache negative browser-support results when deciding whether to merge rules

    Checking whether a selector feature is supported by the target browsers previously skipped the cache whenever the feature was not supported, so every occurrence of an unsupported feature re-ran the browserslist/caniuse lookup. This is now cached, which speeds up rule merging.

  • fix(postcss-discard-empty): remove empty cascade layers when they do not affect the layer ordering

  • fix(postcss-normalize-whitespace): stop dropping the escaped character in a trailing backslash escape

    Keep the whitespace character when a declaration ends in a backslash character followed by a whitespace character and the declaration is the last in its rule, instead of leaving a dangling character and invalid CSS

8.0.6

Patch Changes

  • fix(postcss-minify-selectors): preserve namespaced universal selector

  • fix(postcss-merge-rules): keep the cascade intact when hoisting declarations

  • fix(postcss-merge-rules): decide property conflicts from spec data

    The plugin decides whether to reorder declarations using @webref/css data instead of a name-based heuristic. For example, the plugin now recognizes that font and line-height, border-width and border-left, gap and row-gap, and inset and top conflict, and that a flow-relative property and its physical counterpart override each other.

    The plugin now merges properties that do not override each other, but only share part of the name, such as flexandflex-direction`. Vendor extensions that are not part of a W3C specification still fall back to comparing names.

  • fix(postcss-merge-longhand): improve shorthand merging correctness

    Reject merges producing invalid values for border, margin, or padding; do not confuse math functions with border styles or colors; preserve fallback declarations before functions like env() or calc(); correctly weight !important; and stop resurrecting declarations overridden elsewhere.

  • fix: ensure packages reach registry with correct repository field

  • fix(postcss-merge-rules): merge interleaved declarations correctly

  • fix(postcss-reduce-idents): rewrite identifiers based on spec data

    Which declarations define and reference a custom identifier now comes from @webref/css instead of matching property names against a substring. The plugin no longer leaves a renamed identifier dangling behind:

    • a @counter-style renamed while another rule’s fallback descriptor, or a counter()/counters()/target-counter() argument, still names it by its old name
    • a gridline or grid area named by the grid shorthand, which was never rewritten even though the grid-area placing against it was
    • a gridline named inside repeat() or minmax()
    • a counter the experimental string-set property

    It also no longer renames a keyframe name appearing where it is not allowed, such as animation-timing-function, and only renames the argument of a counter function that names a counter, rather than every word inside it.

    Identifiers identical to a keyword of the property or descriptor, such as an animation called linear, a counter style called inside, or the words of speak-as: words, are now left alone: which of the two a value means depends on the order the grammar is matched in, so renaming it was unsafe.

    The counters the user agent maintains itself, list-item and page, are no longer renamed either.

8.0.5

Patch Changes

  • fix(postcss-merge-longhand): avoid merging border declarations when result is not equivalent

  • fix: update dependencies

8.0.4

Patch Changes

  • fix(postcss-svgo): encode chracters in the correct order

  • fix(postcss-svgo): do not roll our own URI encoding

    Our own code, while producing smaller output, might end up producing the wrong encoding, since it does not encode all characters.

8.0.3

Patch Changes

  • fix(postcss-normalize-url): add missing TypeScript files

  • chore: regenerate all type definitions with TypeScript 7

  • fix: update svgo, autoprefixer and postcss

  • fix: update PostCSS

  • chore: define package.json exports

  • chore: update dependencies

    Update autoprefixer, browserslist, colordx and postcss

8.0.2

Patch Changes

  • chore: update the postcss peer dependency
  • Updated dependencies
    • cssnano-preset-default@8.0.2

8.0.1

Patch Changes

  • fix(postcss-minify-selectors): avoid folding some selectors incorrectly
  • Updated dependencies
    • cssnano-preset-default@8.0.1

8.0.0

Major Changes

  • ea8e33a: chore: drop Node.js 20 support

    Node.js 20 has reached end of life.

  • d7c57da: Removed cssDeclarationSorter from the default preset. It remains enabled in the advanced preset.

    Motivation

    The plugin can cause breakages without notice whenever a new CSS longhand property is released to browsers if it happens to cause a conflict with another longhand property. To ensure safety and predictability, it is no longer enabled by default.

    How to Update

    If you rely on declaration sorting, you can switch to the advanced preset or explicitly enable cssDeclarationSorter in your configuration.

Patch Changes

  • aa11a12: chore: update PostCSS
  • Updated dependencies [aa11a12]
  • Updated dependencies [ea8e33a]
  • Updated dependencies [d7c57da]
    • cssnano-preset-default@8.0.0

7.1.9

Patch Changes

  • fix(postcss-minify-selectors): do not fold non-standard selectors
  • Updated dependencies
    • cssnano-preset-default@7.0.17

7.1.8

Patch Changes

  • 0005443: fix(postcss-minify-selectors): fix wrong behaviour when merging into is()
  • 7e56dba: fix: update postcss
  • Updated dependencies [0005443]
  • Updated dependencies [7e56dba]
    • cssnano-preset-default@7.0.16

7.1.7

Patch Changes

  • fix: publish all dependencies with attestations
  • Updated dependencies
    • cssnano-preset-default@7.0.15

7.1.6

Patch Changes

  • 322ad33: fix: update postcss peer dependency
  • Updated dependencies [322ad33]
    • cssnano-preset-default@7.0.14

7.1.5

Patch Changes

  • fix: update dependencies
  • Updated dependencies [5cb8b09]
    • cssnano-preset-default@7.0.13

7.1.4

Patch Changes

  • fix: improve color conversion precision
  • Updated dependencies
    • cssnano-preset-default@7.0.12

7.1.3

Patch Changes

  • c3e537a: fix: update postcss-selector-parser
  • 5b9af42: fix: update browserslist and autoprefixer
  • Updated dependencies [c3e537a]
  • Updated dependencies [5b9af42]
    • cssnano-preset-default@7.0.11

7.1.2

Patch Changes

  • Updated dependencies
    • cssnano-preset-default@7.0.10

7.1.1

Patch Changes

  • fix: do not strip % sign inside linear()
  • Updated dependencies
    • cssnano-preset-default@7.0.9

7.1.0

Minor Changes

  • Update to SVGO 4.0
  • Update browserslist

7.0.7

Patch Changes

  • 2f03871: fix: update lilconfig and browserslist
  • perf: load default preset on startup
  • 5672148: fix: update PostCSS peer dependency to version without vulnerabilities
  • Updated dependencies [2f03871]
  • Updated dependencies [171b669]
  • Updated dependencies [20f4eb6]
  • Updated dependencies [5672148]
    • cssnano-preset-default@7.0.7

7.0.6

Patch Changes

  • Updated dependencies [024ddef]
  • Updated dependencies [1d65a10]
    • cssnano-preset-default@7.0.6

7.0.5

Patch Changes

  • f14a898: chore: update all dependencies
  • Updated dependencies [dff5c42]
  • Updated dependencies [f14a898]
    • cssnano-preset-default@7.0.5

7.0.4

Patch Changes

  • cssnano-preset-default@7.0.4

7.0.3

Patch Changes

  • Updated dependencies [0c85fa9]
  • Updated dependencies [13fb841]
  • Updated dependencies [08989b0]
    • cssnano-preset-default@7.0.3

7.0.2

Patch Changes

  • cssnano-preset-default@7.0.2

7.0.1

Patch Changes

  • Updated dependencies [2a26e29]
    • cssnano-preset-default@7.0.1

7.0.0

Major Changes

  • 0d10597: chore: drop support for Node.js 14 and 16

Patch Changes

  • Updated dependencies [0d10597]
    • cssnano-preset-default@7.0.0

6.1.2

Patch Changes

  • fix(cssnano-preset-default): update css-declaration-sorter
  • 2f3fb50: chore: update autoprefixer
  • Updated dependencies
    • cssnano-preset-default@6.1.2

6.1.1

Patch Changes

  • cssnano-preset-default@6.1.1

6.1.0

Minor Changes

  • feat: add preset and plugin options for browserslist

Patch Changes

  • fix(cssnano): prevent crash when first preset is already invoked
  • enable “go to definition” via declaration maps
  • fix: add missing type declarations to plugins with options
  • Updated dependencies
    • cssnano-preset-default@6.1.0

6.0.5

Patch Changes

  • 83d3268: chore: update autoprefixer and browerslist
    • cssnano-preset-default@6.0.5

6.0.4

Patch Changes

  • 311eaee: fix(cssnano): set minimum lilconfig version to one without vulnerabilities
    • cssnano-preset-default@6.0.4

6.0.3

Patch Changes

  • 26bbbd3: chore: update minimum browserslist version to 4.22.2
  • 26bbbd3: chore: update postcss-selector-parser to 6.0.13
  • Updated dependencies [9c6b0bc]
    • cssnano-preset-default@6.0.3

6.0.2

Patch Changes

  • 18331a6: fix: update cssnano peer dependency to 8.4.31 to avoid security issue
  • 18331a6: fix: update postcss-calc to 9.0.1 to solve disappearing expressions inside two brackets
  • 18331a6: deps(postcss-svgo): update SVGO to 3.0.5 and update doc
  • 18331a6: chore: update css-declaration-sorter
  • 18331a6: fix(postcss-minify-selectors): prevent mangling of timeline range names
  • 18331a6: fix(postcss-convert-values): keep percent unit in @Property
  • 18331a6: chore(cssnano): update lilconfig to 3.0.0
  • Updated dependencies [18331a6]
    • cssnano-preset-default@6.0.2

6.0.1

Patch Changes

  • chore: updage postcss-calc to version 9
  • fix(postcss-merge-rules): do not merge nested rules
  • Updated dependencies
    • cssnano-preset-default@6.0.1

6.0.0

Major Changes

  • 39a20405: feat!(cssnano): remove yaml config support
  • ca9d3f55: Switch minimum supported Node version to 14 for all packages

Patch Changes

  • Updated dependencies [ca9d3f55]
  • Updated dependencies [ca9d3f55]
    • cssnano-preset-default@6.0.0

5.1.15

Patch Changes

  • fix(postcsss-reduce-initial): fix mask-repeat conversion fix(postcss-colormin): don’t minify colors in src declarations fix(postcss-merge-rules): do not merge conflicting flex and border properties
  • Updated dependencies
    • cssnano-preset-default@5.2.14

5.1.14

Patch Changes

  • fix: update autoprefixer and browserslist
  • fix(postcss-reduce-initial): improve initial properties data
  • Updated dependencies
    • cssnano-preset-default@5.2.13

5.1.13

Patch Changes

  • fix(cssnano): correct return type of cssnano() call

5.1.12

Patch Changes

  • fix: preserve hyphenated property case
  • fix: ensure sorting properties does not break the output
  • fix: recognize ‘constant’ as a function
  • Updated dependencies
    • cssnano-preset-default@5.2.12

5.1.11

Patch Changes

  • fix: preserve constant values
  • Updated dependencies
    • cssnano-preset-default@5.2.11

5.1.10

Patch Changes

  • chore: update TypeScript and improve types
  • fix: preserve similar nested selectors
  • Updated dependencies
    • cssnano-preset-default@5.2.10

5.1.9

Patch Changes

  • fix: preserve more color function fallbacks
  • Updated dependencies
    • cssnano-preset-default@5.2.9

5.1.8

Patch Changes

  • postcss-convert-values: preserve percentage sign on IE 11
  • postcss-minify-params: refactor
  • Updated dependencies
    • cssnano-preset-default@5.2.8

5.1.7

Patch Changes

  • fix: update postcss-merge-longhand. It was skipped by mistake in the previous release.
  • Updated dependencies
    • cssnano-preset-default@5.2.7

5.1.6

Patch Changes

  • fix: preserve border color when merging border properties
  • Updated dependencies
    • cssnano-preset-default@5.2.6

5.1.5

Patch Changes

  • fix: correct package.json dependency version specifier
  • Updated dependencies
    • cssnano-preset-default@5.2.5

5.1.4

Patch Changes

  • fix: preserve custom property case
  • Updated dependencies
    • cssnano-preset-default@5.2.4

5.1.3

Patch Changes

  • fix: do not merge declarations containing custom properties when it might create invalid declarations
  • Updated dependencies
    • cssnano-preset-default@5.2.3

5.1.2

Patch Changes

  • fix: preserve empty custom properties and ensure they work in Chrome
  • Updated dependencies
    • cssnano-preset-default@5.2.2

5.1.1

Patch Changes

  • fix: remove comments with PostCSS 8.4.6 and greater
  • Updated dependencies
    • cssnano-preset-default@5.2.1

5.1.0

Minor Changes

  • feature: add TypeScript type declarations

Patch Changes

  • Updated dependencies
    • cssnano-preset-default@5.2.0

5.0.17

Patch Changes

  • Publish untranspiled CommonJS source
  • Updated dependencies
    • cssnano-preset-default@5.1.12

5.0.16

Patch Changes

  • refactor: replace natural sort with built-in array sort
  • Updated dependencies
    • cssnano-preset-default@5.1.11

5.0.15

Patch Changes

  • refactor: remove getMatch function from cssnano-utils

    The getMatch function allows nested arrays to emulate a map. It is better to replace this function with a regular Map(). It’s unlikely this function is used outside of cssnano as it requires a very specific nested array struture.

  • fix: update postcss-calc to 8.2

    Remove a crash when postcss-calc cannot parse the value

  • Updated dependencies

    • cssnano-preset-default@5.1.10

5.0.14 (2021-12-20)

Bug fixes

  • fix(cssnano): correctly resolve presets in pnpm monorepo (#1269) (6f9c7477eb)

5.0.13 (2021-12-16)

Patch Changes

  • chore(postcss-normalize-url): reduce dependencies (#1255)(a4267dedcd6)
  • fix(postcss-colormin): accept configuration options (#1263)(3b38038007)
  • Updated dependencies
    • cssnano-preset-default@5.1.9

5.0.12 (2021-11-27)

Bug fixes

  • fix(postcss-reduce-initial): update initial values data (#1242) (c6e9f00b785)
  • Updated dependencies
    • cssnano-preset-default@5.1.8

5.0.11 (2021-11-16)

Bug fixes

  • c38f14c3ce3d0: postcss-normalize-url: avoid changing parameter encoding

Chore

  • 31d5c07dc07a4: refactor: drop one-liner dependencies
  • 07172825ffbb4f4: postcss-merge-longhand: drop css-color-names dependency

5.0.10 (2021-11-05)

Bug fixes

  • postcss-merge-longhand: prevent crash in some situations (#1222) (83009a)

5.0.9 (2021-11-01)

Bug fixes

  • postcss-svgo: normalize SVG with escaped quote characters (#1200) (4ef5e41)

  • postcss-convert-values: preserve percentage-only properties (#1212) (8f3453)

  • postcss-minify-gradients: handle 2 color-stop-length in linear gradient (#1215) (8bb7ba6c)

  • cssnano-preset-advanced: update autoprefixer (#1213) (f19932)

Chore

  • postcss-colormin: use colord plugin for color minification (#1207) (3dbaa04)

5.0.8 (2021-08-18)

Chore

  • postcss-minify-gradients: remove extra dependencies (#1181) (50eb53)

5.0.7 (2021-07-21)

Bug fixes

  • cssnano: reduce dependencies by moving from cosmiconfig to lilconfig (#1168) (506a8232)

5.0.6 (2021-06-09)

Bug Fixes

postcss-normalize-url: bump normalize-url dependency to 6.0.1 (#1142) (b60f54bed)

postcss-ordered-values: preserve columns count (#1144) (9acd6a2fe3e)

5.0.5 (2021-05-28)

Bug fixes

  • Preserve alpha channel in color minification
  • Check overlaps more exhaustively when merging rules
  • Do not crash when the input CSS contains relative URLs

5.0.4 (2021-05-21)

Bug Fixes

5.0.3 (2021-05-19)

Bug Fixes

  • cssnano: many bug fixes in dependent packages. Most notably fixed buggy reordering of border declarations and improved color value minification. See the changelogs for the single presets and plugins for details.

5.0.2 (2021-04-26)

Bug Fixes

  • cssnano: replace opencollective with funding field. (#1047) (3dee7c5), closes #1046

5.0.1 (2021-04-13)

Bug Fixes

  • cssnano: replace opencollective with funding field. (#1047) (3dee7c5), closes #1046

5.0.0 (2021-04-06)

Note: Version bump only for package cssnano

5.0.0-rc.2 (2021-03-15)

Bug Fixes

5.0.0-rc.1 (2021-03-04)

Note: Version bump only for package cssnano

5.0.0-rc.0 (2021-02-19)

Bug Fixes

  • postcss-ordered-values: columns transform returning string instead of the AST (#928) (a5d6d36)
  • unique-selector: removed sorting and involving selector comments (#857) (3fa875d)

chore

  • minimum require version of node is 10.13 (#871) (28bda24)

Features

BREAKING CHANGES

  • minimum supported postcss version is 8.2.1
  • minimum require version of node is 10.13

4.1.10 (2019-02-14)

4.1.9 (2019-02-12)

Bug Fixes

4.1.7 (2018-10-22)

4.1.6 (2018-10-22)

4.1.5 (2018-10-17)

Bug Fixes

  • toggling of plugins in presets using boolean configuration option (#622) (15076f1)

4.1.4 (2018-09-27)

4.1.3 (2018-09-25)

4.1.2 (2018-09-25)

4.1.1 (2018-09-24)

Bug Fixes

4.1.0 (2018-08-24)

4.0.5 (2018-07-30)

4.0.4 (2018-07-25)

4.0.3 (2018-07-18)

Bug Fixes

4.1.10

Bug Fixes

  • stylehacks does not throw error on [attr] selector

4.1.9

Performance Improvements

  • postcss-colormin: increase performance
  • postcss-discard-comments: increase performance
  • postcss-merge-rules increase performance
  • postcss-minify-params increase performance
  • postcss-minify-selectors: increase performance
  • postcss-normalize-display-values: increase performance
  • postcss-normalize-positions: increase performance
  • postcss-normalize-repeat-style: increase performance
  • postcss-normalize-string: increase performance
  • postcss-normalize-timing-functions: increase performance
  • postcss-normalize-whitespace: increase performance
  • postcss-ordered-values: increase performance
  • postcss-reduce-transforms: increase performance
  • postcss-svgo: increase performance

Bug Fixes

  • postcss-merge-longhand handle uppercase properties and values
  • postcss-minify-gradients handle uppercase properties and values
  • postcss-minify-params do break @page rules
  • postcss-reduce-idents handle uppercase at-rules
  • postcss-reduce-initial now uses repeat as initial value for mask-repeat
  • postcss-reduce-initial handle uppercase value when you convert to initial
  • stylehacks handle uppercase properties and values

4.1.8

Performance Improvements

  • initial loading time (require('cssnano')).

Bug Fixes

  • postcss-merge-longhand correctly merging border properties with custom properties.

4.1.7

Bug Fixes

  • republish cssnano due broken release.

4.1.6

Bug Fixes

  • postcss-merge-longhand doesn’t throw error when merge a border property.

4.1.5

Bug Fixes

  • cssnano now allow to toggling of plugins in presets using boolean configuration option.
  • postcss-merge-longhand doesn’t merge properties with unset.
  • postcss-merge-longhand correctly merge borders with custom properties.
  • postcss-merge-longhand doesn’t merge redundant values if declarations are of different importance.

Other changes

  • postcss-calc updated to 7.0.0 version.

4.1.4

Other changes

  • css-declaration-sorter now use PostCSS 7.
  • postcss-calc now use PostCSS 7.

4.1.3

Other changes

  • postcss-minify-font-values now use PostCSS 7.
  • postcss-discard-duplicates now use PostCSS 7.

4.1.2

Bug Fixes

  • postcss-svgo now handle DataURI with uppercase data value (DATA:image/*;...).

4.1.1

Bug Fixes

  • css-declaration-sorter was removed from default prevent.
  • postcss-normalize-timing-functions doesn’t lowercased property anymore.
  • postcss-normalize-positons now handles uppercase properties.
  • postcss-normalize-url now is case-insensitive.
  • postcss-merge-idents now is case-insensitive.
  • postcss-merge-rules now is case-insensitive.
  • postcss-minify-selectors now is case-insensitive.
  • postcss-minify-font-values now is case-insensitive.
  • postcss-normalize-unicode now has correct dependencies.
  • postcss-minify-params now has correct dependencies.

Other changes

  • cssnano-preset-advanced use Autoprefixer 9.
  • use PostCSS 7 in all plugins.

4.1.0

Bug Fixes

  • postcss-merge-longhand doesn’t mangle borders.

Features

  • postcss-ordered-values support ordering animation values.

4.0.5

Bug Fixes

  • postcss-merge-longhand now correctly merges borders with custom properties.
  • postcss-merge-longhand doesn’t throw error in some border merge cases.

4.0.4

Bug Fixes

  • postcss-merge-longhand doesn’t drop border-width with custom property from border shorthand.
  • postcss-merge-longhand doesn’t convert currentColor.
  • postcss-merge-longhand doesn’t merge border properties if there is a shorthand property between them.

4.0.3

Bug Fixes

  • postcss-merge-longhand incorrect minification of border (border-*) declarations.

4.0.2

Bug Fixes

  • postcss-merge-longhand don’t explode declarations with custom properties.
  • postcss-colormin now better transform to hsl.

4.0.1

Bug Fixes

  • browserslist version incompatibility with caniuse-api.

4.0.0

Breaking changes

  • We dropped support for Node 4, now requiring at least Node 6.9.

Features

  • postcss-merge-longhand now optimises border-spacing property.

Bug Fixes

  • postcss-normalize-unicode doesn’t change U to lowercase for IE <= 11 and Edge <= 15.
  • postcss-merge-longhand works with custom properties (Example a { border-style:dotted; border-style:var(--variable) }) correctly.
  • postcss-ordered-values handle border property with invalid border width value correctly.
  • postcss-merge-rules handles :-ms-input-placeholder and ::-ms-input-placeholder selectors correctly.
  • postcss-merge-rules works with all property correctly.
  • postcss-normalize-url don’t handle empty url function.
  • postcss-normalize-url handles data and *-extension:// URLs correctly.
  • postcss-colormin adds whitespace after minified value and before function.
  • postcss-minify-font-values better escapes font name.
  • postcss-minify-params doesn’t remove all for IE.

Other changes

  • update all dependencies to latest.
  • better handles uppercase selectors/properties/values/units.

4.0.0-rc.2

Features

  • Includes the new release candidate for postcss-selector-parser 3.
  • Refactors comments tokenizing in postcss-discard-comments to be more memory efficient.
  • Adds css-declaration-sorter for improved gzip compression efficiencies (thanks to @Siilwyn).
  • postcss-svgo now optimises base 64 encoded SVG where possible (thanks to @evilebottnawi).
  • stylehacks now supports @media \0screen\,screen\9 {} hacks (thanks to @evilebottnawi).

Bug Fixes

  • Fixed handling of package.json configuration (thanks to @andyjansson).
  • Fixed resolveConfig for a Root node without a source property (thanks to @darthmaim).
  • Improved radial gradient handling (thanks to @pigcan).
  • stylehacks now properly accounts for vendor prefixes (thanks to @evilebottnawi).

4.0.0-rc.1

Bug Fixes

  • cssnano: Resolved an issue with external configuration which wasn’t being loaded correctly (thanks to @andyjansson).
  • postcss-minify-params: Resolved an issue with cssnano’s handling of the @value syntax from css-modules to better integrate with css-loader.

4.0.0-rc.0

Since version 4 has been in-development for some time, we thought it would be best to release an alpha version so that we could catch any issues before the actual release.

Breaking changes

  • cssnano & its plugins have been upgraded to PostCSS 6.x. Please ensure that for optimal results that you use cssnano with a PostCSS 6 compatible runner & that any other plugins are also using PostCSS 6.

  • cssnano is now essentially a preset loader and does not contain any built-in transforms (instead, it delegates to cssnano-preset-default by default). Due to the new architecture, it’s not possible to exclude asynchronous transforms and run it synchronously, unlike in 3.x. Any transforms that were “core” modules have now been extracted out into separate packages.

  • Because of the new preset system, cssnano will not accept any transformation options; these must be set in the preset. The option names remain mostly the same, except some cases where “core” modules have been extracted out:

    • core is now normalizeWhitespace.
    • reduceBackgroundRepeat is now normalizeRepeatStyle.
    • reduceDisplayValues is now normalizeDisplayValues.
    • reducePositions is now normalizePositions.
    • reduceTimingFunctions is now normalizeTimingFunctions.
    • styleCache is now rawCache.

    When excluding transforms, we now have an exclude option (in 3.x this was named disable). Similarly, the safe option was removed; the defaults are now much less aggressive.

  • By default, the following transforms are no longer applied to any input CSS. You may see an increased output file size as a result:

    • autoprefixer
    • postcss-discard-unused
    • postcss-merge-idents
    • postcss-reduce-idents
    • postcss-zindex

    Note that you can load cssnano-preset-advanced instead which does contain these transforms.

  • We no longer detect previous plugins to silently exclude our own, and now consider this to be an anti-pattern. So postcss-filter-plugins was removed.

  • We also changed some options to make the default transforms safer:

    • postcss-minify-font-values: removeAfterKeyword set to false from true.
    • postcss-normalize-url: stripWWW set to false from true.

  • cssnano now does not accept the sourcemap shortcut option; please refer to the PostCSS documentation on sourcemaps. The quickstart.js file included with this module will give you a good starting point.

  • cssnano.process is no longer a custom method; we use the built-in process method exposed on each PostCSS plugin. The new signature is cssnano.process(css, postcssOpts, cssnanoOpts), in 3.x it was cssnano.process(css, cssnanoOpts).

  • We dropped support for Node 0.12, now requiring at least Node 4.

  • Finally, cssnano is now developed as a monorepo, due to the fact that some transforms have a lot of grey area/overlap. Due to this, some modules have been refactored to delegate responsibility to others, such that duplication of functionality is minimized. For instance, postcss-colormin will no longer compress whitespace or compress numbers, as those are handled by postcss-normalize-whitespace & postcss-convert-values respectively.

Other changes

  • Due to the PostCSS 6 upgrade, we have been able to reduce usage of custom methods, such as node clone behaviour. In cases where some utility has been used by several plugins it is now a separate package, reducing cssnano’s footprint.
  • cssnano now makes much better use of Browserslist. postcss-colormin & postcss-reduce-initial were enhanced with different behaviour depending on which browsers are passed. And now, the footprint for the caniuse-db dependency is much smaller thanks to caniuse-lite - 7 times smaller as of this writing. This makes cssnano much faster to download from npm!

3.10.0

  • cssnano will no longer console.warn any messages when using deprecated options; these are now sent to PostCSS. You will be able to see them if you use a PostCSS runner with built-in messages support, or alternately by loading postcss-reporter or postcss-browser-reporter in your plugins list.
  • Prepares support for grid identifier reduction by adding it to the list of optimisations turned off when options.safe is set to true.
  • Adds support for normalizing unicode-range descriptors. Values will be converted when the code matches 0 & f in the same place on both sides of the range. So, u+2000-2fff can be converted to u+2???, but u+2100-2fff will be left as it is.

3.9.1

  • Resolves an integration issue with v3.9.0, where undefined values would attempt to be parsed.

3.9.0

  • Adds a new option to normalize wrapping quotes for strings & joining multiple-line strings into a single line. This optimisation can potentially reduce the final gzipped size of your CSS file.

3.8.2

  • Resolves an issue where display: list-item inline flow would be normalized to inline list-item rather than inline-list-item (thanks to @mattbasta).

3.8.1

3.8.0

  • Adds support for normalizing multiple values for the display property. For example block flow can be simplified to block.

3.7.7

  • Further improves CSS mixin handling; semicolons will no longer be stripped from rules as well as declarations.

3.7.6

  • Resolves an issue where the semicolon was being incorrectly stripped from CSS mixins.

3.7.5

  • Resolves an issue where the safe flag was not being persisted across multiple files (thanks to @techmatt101).

3.7.4

  • Improves performance of the reducePositions transform by testing against hasOwnProperty instead of using an array of object keys.
  • Removes the redundant indexes-of dependency.

3.7.3

  • Unpins postcss-filter-plugins from 2.0.0 as a fix has landed in the new version of uniqid.

3.7.2

  • Temporarily pins postcss-filter-plugins to version 2.0.0 in order to mitigate an issue with uniqid 3.0.0.

3.7.1

  • Enabling safe mode now turns off both postcss-merge-idents & postcss-normalize-url’s stripWWW option.

3.7.0

  • Added: Reduce background-repeat definitions; works with both this property & the background shorthand, and aims to compress the extended two value syntax into the single value syntax.
  • Added: Reduce initial values for properties when the actual initial value is shorter; for example, min-width: initial becomes min-width: 0.

3.6.2

  • Fixed an issue where cssnano would crash on steps(1).

3.6.1

  • Fixed an issue where cssnano would crash on steps functions with a single argument.

3.6.0

  • Added postcss-discard-overridden to safely discard overridden rules with the same identifier (thanks to @Justineo).
  • Added: Reduce animation/transition timing functions. Detects cubic-bezier functions that are equivalent to the timing keywords and compresses, as well as normalizing the steps timing function.
  • Added the perspective-origin property to the list of supported properties transformed by the reduce-positions transform.

3.5.2

  • Resolves an issue where the 3 or 4 value syntax for background-position were being incorrectly converted.

3.5.1

  • Improves checking for background-position values in the background shorthand property.

3.5.0

  • Adds a new optimisation path which can minimise keyword values for background-position and the background shorthand.
  • Tweaks to performance in the core module, now performs less AST passes.
  • Now compiled with Babel 6.

3.4.0

  • Adds a new optimisation path which can minimise gradient parameters automatically.

3.3.2

  • Fixes an issue where using options.safe threw an error when cssnano was not used as part of a PostCSS instance, but standalone (such as in modules like gulp-cssnano). cssnano now renames safe internally to isSafe.

3.3.1

  • Unpins postcss-colormin from 2.1.2, as the 2.1.3 & 2.1.4 patches had optimization regressions that are now resolved in 2.1.5.

3.3.0

  • Updated modules to use postcss-value-parser version 3 (thanks to @TrySound).
  • Now converts between transform functions with postcss-reduce-transforms. e.g. translate3d(0, 0, 0) becomes translateZ(0).

3.2.0

  • cssnano no longer converts outline: none to outline: 0, as there are some cases where the values are not equivalent (thanks to @TrySound).
  • cssnano no longer converts for example 16px to 1pc by default. Length optimisations can be turned on via {convertValues: {length: true}}.
  • Improved minimization of css functions (thanks to @TrySound).

3.1.0

  • This release swaps postcss-single-charset for postcss-normalize-charset, which can detect encoding to determine whether a charset is necessary. Optionally, you can set the add option to true to prepend a UTF-8 charset to the output automatically (thanks to @TrySound).
  • A safe option was added, which disables more aggressive optimisations, as a convenient preset configuration (thanks to @TrySound).
  • Added an option to convert from deg to turn & vice versa, & improved minification performance in functions (thanks to @TrySound).

3.0.3

  • Fixes an issue where cssnano was removing spaces around forward slashes in string literals (thanks to @TrySound).

3.0.2

  • Fixes an issue where cssnano was removing spaces around forward slashes in calc functions.

3.0.1

  • Replaced css-list & balanced-match with postcss-value-parser, reducing the module’s overall size (thanks to @TrySound).

3.0.0

  • All cssnano plugins and cssnano itself have migrated to PostCSS 5.x. Please make sure that when using the 3.x releases that you use a 5.x compatible PostCSS runner.
  • cssnano will now compress inline SVG through SVGO. Because of this change, interfacing with cssnano must now be done through an asynchronous API. The main process method has the same signature as a PostCSS processor instance.
  • The old options such as merge & fonts that were deprecated in release 2.5.0 were removed. The new architecture allows you to specify any module name to disable it.
  • postcss-minify-selectors’ at-rule compression was extracted out into postcss-minify-params (thanks to @TrySound).
  • Overall performance of the module has improved dramatically, thanks to work by @TrySound and input from the community.
  • Improved selector merging/deduplication in certain use cases.
  • cssnano no longer compresses hex colours in filter properties, to better support old versions of Internet Explorer (thanks to @faddee).
  • cssnano will not merge properties together that have an inherit keyword.
  • postcss-minify-font-weight & postcss-font-family were consolidated into postcss-minify-font-values. Using the old options will print deprecation warnings (thanks to @TrySound).
  • The cssnano CLI was extracted into a separate module, so that dependent modules such as gulp-cssnano don’t download unnecessary extras.

2.6.1

  • Improved performance of the core module functionOptimiser.

2.6.0

  • Adds a new optimisation which re-orders properties that accept values in an arbitrary order. This can lead to improved merging behaviour in certain cases.

2.5.0

  • Adds support for disabling modules of the user’s choosing, with new option names. The old options (such as merge & fonts) will be removed in 3.0.

2.4.0

  • postcss-minify-selectors was extended to add support for conversion of ::before to :before; this release removes the dedicated postcss-pseudoelements module.

2.3.0

  • Consolidated postcss-minify-trbl & two integrated modules into postcss-merge-longhand.

2.2.0

  • Replaced integrated plugin filter with postcss-filter-plugins.
  • Improved rule merging logic.
  • Improved performance across the board by reducing AST iterations where it was possible to do so.
  • cssnano will now perform better whitespace compression when used with other PostCSS plugins.

2.1.1

  • Fixes an issue where options were not passed to normalize-url.

2.1.0

  • Allow postcss-font-family to be disabled.

2.0.3

  • cssnano can now be consumed with the parentheses-less method in PostCSS; e.g. postcss([ cssnano ]).
  • Fixes an issue where ‘Din’ was being picked up by the logic as a numeric value, causing the full font name to be incorrectly rearranged.

2.0.2

  • Extract trbl value reducing into a separate module.
  • Refactor core longhand optimiser to not rely on trbl cache.
  • Adds support for ch units; previously they were removed.
  • Fixes parsing of some selector hacks.
  • Fixes an issue where embedded base 64 data was being converted as if it were a URL.

2.0.1

  • Add postcss-plugin keyword to package.json.
  • Wraps all core processors with the PostCSS 4.1 plugin API.

2.0.0

  • Adds removal of outdated vendor prefixes based on browser support.
  • Addresses an issue where relative path separators were converted to backslashes on Windows.
  • cssnano will now detect previous plugins and silently disable them when the functionality overlaps. This is to enable faster interoperation with cssnext.
  • cssnano now exports as a PostCSS plugin. The simple interface is exposed at cssnano.process(css, opts) instead of cssnano(css, opts).
  • Improved URL detection when using two or more in the same declaration.
  • node 0.10 is no longer officially supported.

1.4.3

  • Fixes incorrect minification of background:none to background:0 0.

1.4.2

  • Fixes an issue with nested URLs inside url() functions.

1.4.1

  • Addresses an issue where whitespace removal after a CSS function would cause rendering issues in Internet Explorer.

1.4.0

  • Adds support for removal of unused @keyframes and @counter-style at-rules.
  • comments: adds support for user-directed removal of comments, with the remove option (thanks to @dmitrykiselyov).
  • comments: removeAllButFirst now operates on each CSS tree, rather than the first one passed to cssnano.

1.3.3

  • Fixes incorrect minification of border:none to border:0 0.

1.3.2

  • Improved selector minifying logic, leading to better compression of attribute selectors.
  • Improved comment discarding logic.

1.3.1

  • Fixes crash on undefined decl.before from prior AST.

1.3.0

  • Added support for bundling cssnano using webpack (thanks to @MoOx).

1.2.1

  • Fixed a bug where a CSS function keyword inside its value would throw an error.

1.2.0

  • Better support for merging properties without the existance of a shorthand override.
  • Can now ‘merge forward’ adjacent rules as well as the previous ‘merge behind’ behaviour, leading to better compression.
  • Selector re-ordering now happens last in the chain of plugins, to help clean up merged selectors.

1.1.0

  • Now can merge identifiers such as @keyframes and @counter-style if they have duplicated properties but are named differently.
  • Fixes an issue where duplicated keyframes with the same name would cause an infinite loop.

1.0.2

  • Improve module loading logic (thanks to @tunnckoCore).
  • Improve minification of numeric values, with better support for rem, trailing zeroes and slash/comma separated values (thanks to @TrySound & @tunnckoCore).
  • Fixed an issue where -webkit-tap-highlight-color values were being incorrectly transformed to transparent. This is not supported in Safari.
  • Added support for viewport units (thanks to @TrySound).
  • Add MIT license file.

1.0.1

  • Add repository/author links to package.json.

1.0.0

  • Initial release.