`build --watch` doesn't refresh changes made to css dependencies

[gabrielfin]

Describe the bug

When modifying an asset referenced in a CSS file, a rebuild is triggered, but the asset included in the build is not the updated version.

So, for example, modifying an image included with url(...), will trigger a new build, but the image in the build is still the old one.

I have looked for an issue related to this bug, but haven't found any, which is odd since it's a very common use case. Maybe I'm using the wrong terms or doing something wrong.

Reproduction

https://stackblitz.com/edit/vitejs-vite-5jtq9ym7?file=src%2Faa.svg

Steps to reproduce

1. Run vite build --watch
2. Modify src/aa.svg (for example clear the contents) and save

Expected result:
A build is generated, aa-[hash].svg should get a new hash, and it's contents should be empty (0.00 kB)

Actual result:
A build is generated, but nothing has changed. aa-[hash].svg has the same hash as before, and it still is 1.00 kB

System Info

System:
    OS: Linux 6.8 Ubuntu 24.04.2 LTS 24.04.2 LTS (Noble Numbat)
    CPU: (4) x64 Intel(R) Core(TM) i5-3450 CPU @ 3.10GHz
    Memory: 8.71 GB / 15.57 GB
    Container: Yes
    Shell: 5.2.21 - /bin/bash
  Binaries:
    Node: 22.14.0 - ~/.nvm/versions/node/v22.14.0/bin/node
    npm: 10.9.2 - ~/.nvm/versions/node/v22.14.0/bin/npm
  npmPackages:
    vite: ^6.3.1 => 6.3.1

Used Package Manager

npm

Logs

No response

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• The provided reproduction is a minimal reproducible example of the bug.