Debug CSS optimization warnings

CSS optimization warnings are rare in Framer. In most cases, they are caused by custom code components that rely on private Framer APIs. In some cases, they can also point to an issue in Framer itself.

About this warning

In August and September 2025, Framer introduced a new CSS optimizer. Some older component versions were not compatible with this optimizer, including older versions of components such as Vimeo and Code Block. Current Framer components are compatible with the new CSS optimizer.

For more background on custom code compatibility, see Custom Code.

What the warning looks like

You might see a warning like this:

How to debug the issue

Start by checking whether any components in your project have updates available. If updates are available, install them and then publish or preview your site again to confirm whether the warning is resolved.

If all components are already up to date and the warning still appears, contact our support team. This can help confirm whether the issue is caused by a project-specific component or an underlying bug in Framer. When you contact support, include the full warning message and note whether you have already updated all components in the project. This makes it easier to investigate the cause and speed up troubleshooting.