Troubleshooting
No classes appear
Confirm that the sitepackage registers the manifest and that its generated file exists at the registered path. In a Development context the connector reports a missing registration or file as a PHP notice or warning. Rebuild the frontend assets, then flush TYPO3 caches.
An unknown style key returns no classes. Enable warn and use a
Development context to see the available keys in the warning. Check spelling
and make sure the corresponding StyleX source file is imported by the Vite
entrypoint.
Styles do not show during Vite development
Ensure the browser receives /virtual: from the Vite server. See
Vite and asset delivery for the runtime link example. The connector
resolves class names but does not serve CSS.
Bootstrap or FSC wins the cascade
Inspect the element's computed styles and the compiled selector. If Bootstrap
is unlayered, set use in the StyleX Vite plugin. If the
project uses named layers, make sure both stylesheets actually use the layer
order declared first in the consuming CSS build. See Bootstrap and cascade layers.
Fluid prints the ViewHelper expression
Check that the extension is active and that TYPO3 caches have been cleared
after installation. The extension registers the stylex namespace globally.
When a conditional uses a nested variable, assign it to an f: and
use that simple name as the when key.
Manifest changes remain stale
In Development, the cache lifetime is already zero. In other contexts, flush
TYPO3 caches after deploying a changed manifest or set an appropriate
manifest in Extension Manager configuration.