Impact Score: 5/10
Tailwind CSS v4.0.15 — Release Notes & Engineering Impact
Source available — automated, not human-reviewed
Component: tailwind · Channel: stable. Automated analysis, not a compatibility certification. How this works.
Analysis updated: 2026-11-01.
⚡ Executive Summary (TL;DR)
Tailwind CSS v4.0.15. Source highlight: Fix incorrect angle in `-bg-conic-*` utilities (#17174)
Who Does This Impact? (Role-Based Analysis)
💻 Software Engineers & Devs
Check the source notes against the package and APIs you use before upgrading.
📊 Product & Engineering Leads
Use the documented changes to assess relevance to your product; release frequency alone is not a quality measure.
⚙️ DevOps & Security
Verify the target version, runtime requirements and rollback procedure in the official documentation.
🔧 Bug Fixes & Patches (6)
- Fix incorrect angle in `-bg-conic-*` utilities (#17174)
- Fix `border-[12px_4px]` being interpreted as a `border-color` instead of a `border-width` (#17248)
- Work around a crash in Safari 16.4 and 16.5 when using the default Preflight styles (#17306)
- Pre-process `<template lang="…">` in Vue files (#17252)
- Ensure that all CSS variables used by Preflight are prefixed (#17036)
- Prevent segfault when loaded in a worker thread on Linux (#17276)
📄 View Raw Release Notes (Original Developer Log)
### Fixed
- Fix incorrect angle in `-bg-conic-*` utilities ([#17174](https://github.com/tailwindlabs/tailwindcss/pull/17174))
- Fix `border-[12px_4px]` being interpreted as a `border-color` instead of a `border-width` ([#17248](https://github.com/tailwindlabs/tailwindcss/pull/17248))
- Work around a crash in Safari 16.4 and 16.5 when using the default Preflight styles ([#17306](https://github.com/tailwindlabs/tailwindcss/pull/17306))
- Pre-process `<template lang="…">` in Vue files ([#17252](https://github.com/tailwindlabs/tailwindcss/pull/17252))
- Ensure that all CSS variables used by Preflight are prefixed ([#17036](https://github.com/tailwindlabs/tailwindcss/pull/17036))
- Prevent segfault when loaded in a worker thread on Linux ([#17276](https://github.com/tailwindlabs/tailwindcss/pull/17276))
- Ensure multiple `--value(…)` or `--modifier(…)` calls don't delete subsequent declarations ([#17273](https://github.com/tailwindlabs/tailwindcss/pull/17273))
- Fix class extraction followed by `(` in Slim ([#17278](https://github.com/tailwindlabs/tailwindcss/pull/17278))
- Export `PluginUtils` from `tailwindcss/plugin` for compatibility with v3 ([#17299](https://github.com/tailwindlabs/tailwindcss/pull/17299))
- Remove redundant `line-height: initial` from Preflight ([#15212](https://github.com/tailwindlabs/tailwindcss/pull/15212))
- Increase Standalone hardware compatibility on macOS x64 builds ([#17267](https://github.com/tailwindlabs/tailwindcss/pull/17267))
- Ensure that the CSS file rebuilds if a new CSS variable is used from templates ([#17301](https://github.com/tailwindlabs/tailwindcss/pull/17301))
### Changed
- The `--theme(…)` function now returns CSS variables from your theme variables unless used inside positions where CSS variables are invalid (e.g. inside `@media` queries) ([#17036](https://github.com/tailwindlabs/tailwindcss/pull/17036))