Cookie Keeper — Cookie backup to localStorage

What is Cookie Keeper?

Cookie Keeper is an add-on that automatically backs up critical tracking cookies (GA4, Meta Pixel, TikTok, etc.) to localStorage and restores them if the browser deletes them.

Why use Cookie Keeper?

• Safari ITP: Intelligent Tracking Prevention trims cookies to 7 days.
• Firefox ETP: Enhanced Tracking Protection blocks cross-site cookies.
• Loss of attribution: Without cookies, GA4 loses 20-30% of returning visitors.
• ROI: Restoring cookies = better attribution = more accurate ROAS.

How to activate

1. Go to Dashboard → Add-ons
2. Turn on the "Cookie Keeper" toggle
3. Select the standard cookies to back up (GA4, Meta, TikTok, Google Ads, etc.)
4. Add custom cookies (a JSON array, e.g. ["_my_custom_cookie", "_another"])
5. Set the retention period (recommended: 730 days = 2 years)
6. Optionally: set a custom cookie domain (e.g. .yourdomain.cz)
7. Click "Save Cookie Keeper"

Which cookies get backed up?

Standard cookies:

• _ga, _ga_* — GA4 Client ID and session
• _fbp, _fbc — Meta Pixel browser ID and click ID
• _ttp — TikTok Pixel
• _gcl_au, _gcl_aw, _gcl_dc — Google Ads
• sbjs_* — Sourcebuster.js (attribution)

How does it work?

1. The Cookie Keeper script runs on every page
2. Periodically (every 5s) it checks for the existence of the cookies
3. If a cookie exists → it saves a copy to localStorage
4. If a cookie is missing → it restores it from localStorage
5. The localStorage record validity: 2 years (configured)