When a Chrome extension “does nothing” on one website—no icon behavior, no blocker, no helper panel—it’s usually a permission or site rule issue, not a broken extension.
Start with a quick mobile-first check (to confirm what’s even possible), then switch to desktop steps where extensions actually run.
Before you change anything: note the site URL, the extension name, and whether it fails on one site or everywhere.
1. Mobile-first: confirm whether extensions can run on your device
If you’re testing on a phone first, this matters.
- Chrome on iPhone/iPad: traditional Chrome desktop extensions do not run.
- Chrome on Android: Chrome mobile generally does not support desktop extensions.
- What to do instead: try the site in Chrome on a computer, or use an app/feature built for mobile (for example, content blockers in Safari on iOS, or DNS-level blockers).
If the extension is “not working” only because you’re on mobile, the fix is simply using a supported platform.
2. Desktop: verify the extension is enabled and allowed in Incognito (if needed)
This is the fastest “it was off” check.
- Open Chrome and go to chrome://extensions.
- Make sure the extension toggle is On.
- If you’re using an Incognito window, open the extension’s details and enable Allow in incognito (only if you truly need it).
A surprising number of issues are just Incognito restrictions or a disabled toggle after an update.
3. Desktop: check the extension’s “Site access” for that specific website
Many extensions intentionally do nothing unless you allow them on the current site.
- Click the Extensions (puzzle piece) icon in Chrome.
- Find the extension, then open its options/details.
- Look for Site access settings such as “On click”, “On specific sites”, or “On all sites”.
- Add the site that’s failing (use the exact domain you’re visiting).
If the site uses multiple subdomains (for example, login.example.com and app.example.com), you may need to allow more than one.
4. Desktop: rule out built-in browser settings that block extension behavior
Chrome privacy and site settings can prevent extensions from interacting with pages.
- Pop-ups/redirects blocked: can break coupon, SSO, or helper extensions.
- Cookies blocked: can break extensions that depend on session state.
- JavaScript blocked: many extensions rely on it to inject scripts.
- Enhanced protection / strict settings: may reduce extension functionality on some sites.
Try temporarily relaxing only what’s necessary for that one site, then revert if it doesn’t help.
5. Desktop: test for extension conflicts (one-site failures often are)
Two extensions can fight over the same page elements (common with ad blockers, password tools, script/privacy tools).
- Open chrome://extensions.
- Turn off similar extensions one at a time (keep notes).
- Reload the problem site after each change (Ctrl+R / Cmd+R).
If the site starts working, re-enable extensions carefully until you find the conflicting pair.
6. Desktop: clear the site’s data (targeted reset without wiping everything)
If the extension depends on the site being in a clean state, corrupted cookies/local storage can make it look like the extension is failing.
- Open the site.
- Click the lock icon in the address bar → site settings.
- Clear site data for that domain (or use Chrome settings to clear data for one site).
- Sign in again and retest the extension.
This is safer than clearing all browsing data.
7. Desktop: try a clean profile or Guest mode (fast way to separate profile issues)
Profiles accumulate policies, sync settings, and extension state that can break things over time.
- Open Chrome’s profile menu and choose Guest, or create a new temporary profile.
- Install only the one extension you’re testing.
- Visit the site and check whether it works there.
If it works in Guest/new profile, your main profile likely has a conflict, corrupted extension data, or a setting that blocks it.
Final thoughts
On mobile, most “extension not working” reports are simply platform limitations. On desktop, the usual fix is site access permissions or a conflict with another extension.
If nothing helps, remove and reinstall the extension, then re-check its site access settings before testing again.