Troubleshoot issues with the visual editor

Fix visual editor loading issues, slowness, or errors.

The visual editor is the part of the Optimize dashboard that lets you preview webpages and create variations. If the visual editor is slow, unresponsive, unable to load a webpage, or displays a generic error message, use this guide to help identify the cause.

Check your allowed domains list

Optimize has an allowed domains setting that allows you to allowlist different parts of your website (i.e., domains or subdomains). If the webpage is hosted on a domain or subdomain that's not included in your allowed domains list, the webpage can’t be loaded in the visual editor.

Ensure your webpage's domain/subdomain is on the allowed domains list.

Browser-related issues

Use an updated version of Google Chrome

Google Chrome is the only fully supported browser for Optimize's visual editor. If you're using a different browser or an outdated version of Chrome, it can cause issues with the visual editor.

1. Get the latest update for Chrome
2. Try to reproduce the issue with Chrome

Install the Webflow Optimize assistant

The Webflow Optimize assistant is a Google Chrome extension that adds additional functionality to your web browser to support the visual editor. With the assistant, you can more seamlessly preview webpages and create variations for page elements.

• Download the Webflow Optimize assistant from the Chrome web store
• Learn more about the Webflow Optimize assistant extension

Check for conflicting Chrome browser extensions

A Google Chrome extension may be conflicting with the visual editor. Follow these steps to check for a conflict and, if one exists, identify which extension is causing the issue.

Disable all extensions:

1. Click the Options icon at the top of Chrome
2. Click More Tools > Extensions
3. Toggle Off every extension except the Webflow Optimize assistant
4. Refresh the visual editor page and try to reproduce the issue

Did the issue still happen?

• Yes — you can reenable the extensions and try another troubleshooting method
• No — an extension is responsible and you can use the next steps to isolate which one

Isolate the conflicting extension:

1. Toggle one extension back On
2. Refresh the visual editor page and try to reproduce the issue
3. Repeat steps 1 and 2 above, adding a new extension each time until the issue occurs

The last Chrome extension you turned on is conflicting with the visual editor. Temporarily disable just that extension when using the visual editor going forward.

Network-related issues

Disable your VPN

Depending on the connection and configuration, a VPN can prevent the visual editor from working properly by blocking or interfering with required resources. For example, some VPNs may:

• Introduce latency or connection instability
• Block, reroute, or modify network requests
• Enforce stricter security policies that limit what webpages and embedded content can do
• Override your DNS settings, which may prevent some domains from resolving correctly

If you use a VPN, try to reproduce the issue with the VPN disabled.

Check your network connection speed

A slow or unstable internet connection can prevent the visual editor from loading properly.

You can use online tools that run in the browser to check your internet speed. Just do a web search for "speed test." You should get a general report on whether your internet is slow or fast.

If it's slow and you're on wifi, try moving closer to the router or switching to a wired connection.

Try another network

If your current network connection is unstable or has a custom configuration—such as strict firewall rules or security policies—it may prevent the visual editor from functioning properly. To rule this out, try reproducing the issue on a different network.

For example, if you’re working from a corporate office, consider switching to a home wifi or a public network (like one at a coffee shop) to see if the issue persists.

Site-related issues

Ensure required site cookies allow third-party context

If some of your site pages require cookies and your site is not configured to allow third-party context for cookies, then the visual editor may not be able to properly load the webpage.

Optimize loads webpages in an iframe, which is considered third-party context.

Learn how to fix these types of cookie issues.

Your Content Security Policy (CSP) is blocking Optimize

A Content Security Policy (CSP) essentially tells the visitor's browser what type of content to allow and where to allow it from. The policy is made up of multiple directives (i.e. script-src, frame-src, etc.) that allow certain content from specific domains. For organizations that have a CSP, certain policy directives must be configured to allow Optimize to run properly.

Learn more about updating your CSP to work with Optimize.

JavaScript-related issues

If the Optimize JavaScript snippet isn’t properly installed, or if there’s a conflict within your site’s code, Optimize may not function as expected. Here are a few things to check:

• Ensure the Optimize snippet is correctly installed. Double-check that the code is present and placed in the appropriate part of the page.
• If you’re using a tag manager (e.g., Google Tag Manager), try installing the snippet directly in the page <head> instead, bypassing the tag manager to rule out any issues it might introduce.
• Check for conflicts with third-party JavaScript. Services like consent management platforms or security tools may block or interfere with Optimize. Temporarily disabling these can help determine if they’re the source of the conflict.