Issues

• A calc() in a resolution media feature is a parse error

  parcel-bundler/lightningcss#1406 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• calc(NaN * 1px) prints as 5.10424e38px, so a NaN a browser censors to 0 becomes the largest length

  parcel-bundler/lightningcss#1405 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• With errorRecovery, a declaration whose value fails its property's grammar is kept, and no warning is reported

  parcel-bundler/lightningcss#1404 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• A three-value transform-origin loses its z when its y is a near side: left top 30px minifies to 0 30px

  parcel-bundler/lightningcss#1403 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• calc(1 + 1px) is kept as a valid length, and sign(1em) is folded to 1 at build time

  parcel-bundler/lightningcss#1402 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• A transition list keeps the first of a repeated property, where the last one applies

  parcel-bundler/lightningcss#1401 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• none beside other entries of transition-property or of a transition list parses as a valid value

  parcel-bundler/lightningcss#1400 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• A calculation that divides by zero is rejected, so @media (min-width: calc(1px / 0)) is an error

  parcel-bundler/lightningcss#1399 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• An unparsed value prints -0 as 0, so a division by it flips the sign of its infinity

  parcel-bundler/lightningcss#1398 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• font-weight: calc(2000) minifies to 2000, a value outside the property's range that the browser drops

  parcel-bundler/lightningcss#1397 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• @media not (width = 10px) is printed as @media (width = 10px)

  parcel-bundler/lightningcss#1396 · Filter by author YevheniiKotyrlo opened on Oct 28, 2026

• A relative color's hue keyword is typed as an angle, so tan(h) computes in degrees and calc(h + 10) stays unresolved

  parcel-bundler/lightningcss#1395 · Filter by author YevheniiKotyrlo opened on Oct 27, 2026

• Numbers print with six significant digits, which changes values written with more and prints 10e-23

  parcel-bundler/lightningcss#1394 · Filter by author YevheniiKotyrlo opened on Oct 27, 2026

• Adding a length to a long calc() sum that does not fold takes time quadratic in its terms

  parcel-bundler/lightningcss#1393 · Filter by author YevheniiKotyrlo opened on Oct 27, 2026

• A fallback declaration is dropped before a relative color that cannot be resolved, even for targets without relative color syntax

  parcel-bundler/lightningcss#1392 · Filter by author YevheniiKotyrlo opened on Oct 27, 2026

• position with a CSS-wide keyword (unset/initial/inherit/revert) is emitted before an earlier position value

  parcel-bundler/lightningcss#1391 · Filter by author gabrielrobert opened on Oct 26, 2026

• Parsing nested calc() that contains a var() takes exponential time

  parcel-bundler/lightningcss#1389 · Filter by author Ice-Hazymoon opened on Oct 26, 2026

• Parse time doubles with each nested light-dark() in a custom property

  parcel-bundler/lightningcss#1382 · Filter by author BartWaardenburg opened on Oct 22, 2026

• Custom property color fallbacks (@supports) are dropped for declarations after a nested rule

  parcel-bundler/lightningcss#1381 · Filter by author unotovive opened on Oct 22, 2026

• Minify: whitespace around * and / in calc() with var() is no longer removed (size regression since 1.31)

  parcel-bundler/lightningcss#1378 · Filter by author TomasSlama opened on Oct 19, 2026

• Excluding DirSelector also disables unrelated selector-list splitting and autofill prefixing

  parcel-bundler/lightningcss#1375 · Filter by author codecaaron opened on Oct 16, 2026

• errorRecovery reports a false EndOfInput warning for name-only @container rules

  parcel-bundler/lightningcss#1370 · Filter by author sokra opened on Oct 12, 2026

• Minifier folds animation-timeline into the animation shorthand when no targets are set

  parcel-bundler/lightningcss#1369 · Filter by author kennethyeaher opened on Oct 12, 2026
  2

• color-mix() treats none as 0 when the color carrying it is in a different space than the mix

  parcel-bundler/lightningcss#1368 · Filter by author oddharsh opened on Oct 11, 2026

• @media (min-width) is rewritten to @media (width), which always matches

  parcel-bundler/lightningcss#1366 · Filter by author YevheniiKotyrlo opened on Oct 10, 2026