guides

Protect cookies from changes (planned)

Planned — pin a cookie's value so a site can't silently change or delete it while you debug. Not shipped yet.

What it will do

Mark a cookie as protected and SessionCourier will pin its current value. A background worker will watch the browser’s cookie-change events, and if the site (or anything else) overwrites or deletes the protected cookie, SessionCourier will write the protected value back. Protected cookies will be flagged in the list, so you always see which values are pinned.

When it will help

• Keep a session alive while clearing other state. Protect the session cookie, then clear the rest — you stay logged in while everything else resets.
• Pin an A/B-test or feature-flag cookie to one variant. The site can’t silently rotate you into a different bucket mid-test.
• Stop a misbehaving script from logging you out mid-debug. If some code path keeps clobbering your session cookie, protection restores it faster than you can re-login.

Limits (by design)

Protection will be a debugging aid, not a security boundary. Restoration reacts after a change happens — a request may go out with the changed value before SessionCourier restores it. And if the server invalidates the session on its side, restoring the cookie’s value in the browser can’t bring the session back.

Status

Not shipped yet. Cookie protection is planned, not part of the current build. Today you can already export a session and re-import it to restore it by hand — see import and export cookies. Join the waitlist to hear when protection lands.