#16784·Tailwind CSS

npx watch is case sensitve

Author: SiphonophoraCreated Feb 24, 2025Updated Mar 30, 2026

Version 4.0.7

What build tool (or framework if it abstracts the build tool) are you using?

CLI only npx tailwindcss

What version of Node.js are you using?

v16.20.2

What browser are you using?

Chrome

What operating system are you using?

Windows

Reproduction URL https://github.com/Siphonophora/tailwind-watch-case-sensitive-repo

Describe your issue

When running the --watch command, it does not rebuild when the input file string has casing that is different than the actual casing. So, case insensitivity of windows paths is being only partially honored. Feels like it would be fine if this generated an error, but it appearing to build but failing was pretty confusing.

  • This has paths with the correct casing. Works as expected npx tailwindcss -i ./styles/site.css -o ./build/output.css --watch
  • When there are casing issues, including the examples below, the output is generated once. File changes still lead to Done in ##ms messages, even when the input with the casing issue is what changed. However, output never changes after the initial run.
    • npx tailwindcss -i ./Styles/site.css -o ./build/output.css --watch
    • npx tailwindcss -i ./styles/Site.css -o ./build/output.css --watch
  • Casing issue on the output file path doesn't cause a problem
    • npx tailwindcss -i ./styles/site.css -o ./Build/output.css --watch

Source: tailwindlabs/tailwindcss