If the Appcues builder won't load, causes your page to flicker, or shows an error when you click "Open in Builder," work through the sections below in order. Most issues are resolved in the first three steps.

Quick checks

Before diving into specific symptoms, rule out the most common causes:

1. Is your Chrome browser up to date? Open chrome://settings/help — Chrome should show "Chrome is up to date." If not, update and restart.
2. Is the Appcues Chrome Extension up to date? Right-click the Appcues extension icon > Manage Extension. Click Update at the top of the extensions page. If no update button appears, you're current.
3. Are you logged into Appcues? Click the Appcues extension icon. If you see a login prompt, sign in. The builder cannot load without an active session.
4. Does your page load normally without the extension? Disable the Appcues extension and reload the page. If the page still has issues, the problem is on the site side, not Appcues.

Builder won't load or spins indefinitely

You click "Open in Builder" from Studio or the Chrome Extension, and the builder overlay never appears — the page shows a loading spinner that never resolves.

Clear extension cache and reinstall

1. Go to chrome://extensions/ and find the Appcues Builder extension.
2. Click Remove to uninstall it.
3. Clear your browser cache: open chrome://settings/clearBrowserData, select Cached images and files, and clear.
4. Reinstall the extension from the Chrome Web Store.
5. Log back into Appcues when prompted and try opening the builder again.

Check for conflicting extensions

Other Chrome extensions can interfere with the builder by injecting scripts or modifying page behavior. Common culprits:

• Ad blockers (uBlock Origin, AdBlock Plus) — may block Appcues scripts loaded from fast.appcues.com
• Privacy extensions (Privacy Badger, Ghostery) — may block third-party scripts
• Grammar checkers (Grammarly, LanguageTool) — inject UI into text fields, which can conflict with the builder's text editor
• Password managers (LastPass, 1Password, Dashlane) — add icons to input fields that overlap with builder controls
• Text expanders or clipboard managers — alter input behavior

To test: open an Incognito window with only the Appcues extension enabled (go to chrome://extensions/, toggle Allow in Incognito for the Appcues extension). If the builder loads in Incognito, a conflicting extension is the cause. Re-enable your other extensions one at a time to identify which one.

Verify Content Security Policy (CSP) headers

If your application sets strict CSP headers, the builder may be blocked from loading its scripts or styles. The Appcues builder requires these domains to be allowed:

• *.appcues.com
• *.appcues-static.com

Check your browser console (F12 > Console tab) for CSP violation errors that mention appcues. If you see them, ask your development team to add these domains to your CSP script-src and style-src directives. See Configure Content Security Policies for more details. 

"Credentials not found" after selecting a hosting environment

When you open the builder, it asks you to select the Appcues hosting environment where your account was set up. After you select one, the builder shows Credentials not found and you can't edit. Reinstalling the extension doesn't clear it.

1. Open chrome://settings/help and install any available Chrome update. Restart Chrome.
2. Sign out of Studio, then sign back in.
3. Open the experience in the builder again and select your hosting environment.

Confirm: The builder opens and you can edit the experience.

If the error continues:

• Check that you selected the right environment. The hosting environment only decides where Appcues stores your account's data. Where you, your company, or your users are located doesn't affect which one to pick. Accounts are in the US environment unless EU hosting was requested at setup, and EU accounts sign in at studio.eu.appcues.com. See Appcues US and EU Hosting environments.
• Check that you're signed in to Studio with the same email address that has access to the account. The error means the builder couldn't find your login in the environment you selected.

Builder doesn't auto-open from Studio

You click "Open in Builder" from Studio but the builder never launches — or dozens of tabs open instead of one. This is related to Chrome's permission prompt for the extension to auto-open tabs.

Symptoms:

• Clicking a flow/pin/banner in Studio opens many duplicate tabs
• The permission modal appears in Studio but clicking "Allow" does nothing
• The extension's permission settings page shows a toggle instead of the expected "On all sites" dropdown

Fix:

1. Right-click the Appcues Builder extension icon in Chrome's toolbar and select Automatically open the Builder. Chrome should show a native permission prompt — click Allow.
2. If no native prompt appears, your Chrome or OS configuration is blocking it. This is a known Chrome-side issue, not an Appcues bug.
3. As a workaround, disable auto-open and open the builder manually: navigate to the page where your experience targets, then click the Appcues extension icon to launch the builder from that page directly.

Builder loads but content won't save

You can open the builder and edit, but changes don't persist after saving.

1. Check your browser console for network errors — look for failed requests to api.appcues.com.
2. Make sure you're editing the correct version. If the experience is published, the builder opens a draft. Your edits save to the draft until you explicitly publish.
3. Try logging out of Appcues and back in — your session token may have expired.

"Something went wrong" error screen

If you see a full-screen error message when opening the builder:

1. Uninstall and reinstall the Chrome Extension (see steps above).
2. Log out of Appcues by clicking settings > Log out.
3. Re-open the builder. You'll be prompted to log in again.
4. If the error persists, clear all browsing data (not just cache) for the last hour at chrome://settings/clearBrowserData and try again.

Extension installed but icon is missing

If you installed the extension but don't see the Appcues icon in Chrome's toolbar:

1. Click the puzzle piece icon (Extensions menu) in Chrome's toolbar.
2. Find Appcues and click the pin icon to pin it to the toolbar.
3. If Appcues doesn't appear in the list, go to chrome://extensions/ and confirm it's installed and enabled.

Still stuck?

If none of the above resolves your issue, contact support@appcues.com with:

1. What you see — screenshot or screen recording of the issue
2. Chrome version — from chrome://settings/help
3. Extension version — right-click the Appcues icon > Manage Extension
4. Console errors — open F12 > Console, reproduce the issue, and screenshot any red errors
5. Whether the issue reproduces in Incognito with only the Appcues extension enabled