Using vite vanilla js+tailwindcss in JIT mode + vite-handlebars-plugin: changes in partials doesn't trigger postcss

[carrrramba]

Describe the bug

This seems similar behaviour to the plugin-vue fix #6987 and the described bug with pug templating in #4588

In dev server mode: if i add tailwind css classes to a handlebars template file, the css doesn't get updated. (postcss doesn't get called?). As soon as i change/reload the html file that includes the partial, the css get's updated.
Demo on stackblitz: https://stackblitz.com/edit/vitejs-vite-acozht?file=index.html

...hope this helps :)

Reproduction

https://stackblitz.com/edit/vitejs-vite-acozht?file=index.html

System Info

System:
    OS: macOS Mojave 10.14.6
    CPU: (8) x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz
    Memory: 1.47 GB / 16.00 GB
    Shell: 3.2.57 - /bin/bash
  Binaries:
    Node: 14.19.1 - ~/.nvm/versions/node/v14.19.1/bin/node
    npm: 6.14.16 - ~/.nvm/versions/node/v14.19.1/bin/npm
  Browsers:
    Chrome: 102.0.5005.115
    Firefox: 101.0.1
    Safari: 12.1.2
  npmPackages:
    vite: ^3.0.0-beta.2 => 3.0.0-beta.2

Used Package Manager

npm

Logs

No response

Validations

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• Read the Contributing Guidelines.
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• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.

[jonatanklosko]

Also see alexlafroscia/vite-plugin-handlebars#192.

[sapphi-red]

Yes, it is expected that this happens if handleHotUpdate returns [].

Closing as it is not a bug in Vite.