How to debug CSS optimization warnings
CSS optimization errors are very rare. They are usually caused by custom code components using private Framer APIs. In rare cases they might indicate a bug in Framer.
In Aug-Sep 2025, Framer has released a new CSS optimizer. This optimizer isn’t compatible with some older versions of some components, such as Vimeo and Code Block from Framer. All current Framer components are compatible with the new CSS optimizer.
If you see the error below:
Check if there’s an update available for components, and update them.
Reach out to Framer Support if all components are up-to-date, and the issue still persists
What should I do if I see a CSS optimization error in Framer?
If you see a CSS optimization error, check if there’s an update available for your components and update them. If all components are up-to-date and the issue still persists, reach out to Framer Support.
Which Framer components are affected by the new CSS optimizer?
The new CSS optimizer isn’t compatible with some older versions of certain components, such as Vimeo and Code Block from Framer. All current Framer components are compatible with the new CSS optimizer.
How can I resolve the 'Unexpected token Function("var")' error in Framer?
To resolve the 'Unexpected token Function("var")' error, update any affected components to their latest versions. If the problem continues after updating, contact Framer Support for further assistance.
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