Parallel Accounts par GosuCode

Parallel Accounts lets you run multiple accounts for the same site at once, each in its own Firefox container (contextual identity) — cookies, localStorage, and login sessions stay fully isolated per profile.

Features:

Per-profile containers — every saved profile opens in its own isolated container tab, no cross-contamination between accounts
Encrypted password vault — credentials encrypted at rest (PBKDF2 + AES-GCM) behind a master password you set; the decryption key lives only in memory for the session, never written to disk
Autofill — once the vault is unlocked, saved credentials fill automatically on the profile's login page
CSV export/import — back up or migrate profiles, gated behind master password verification
Vault reset — forgot your master password? Reset clears saved passwords while keeping profile names, emails, URLs, and containers intact
One-click profile deletion with confirmation
Permissions used

contextualIdentities — create and manage one container per profile
cookies — check container-scoped cookie state
tabs — open and track each profile's isolated tab
storage — persist profiles and the encrypted vault
Firefox only — relies on the contextualIdentities API, which has no Chrome equivalent.

No data leaves your browser. No accounts, no telemetry, no external servers.