Learning objectives
After reading this article you will be able to:
- Identify the boundary created by profile storage
- Recognize shared device and network signals
- Check separation without exposing account credentials
What profiles normally keep separate
Cookies and site storage belong to a particular browser context.
| Usually separate between ordinary profiles | Can remain shared |
|---|---|
| Cookies and site login sessions | Public IP address and network route |
| Local storage and IndexedDB | Operating system and installed system fonts |
| Browsing history and bookmarks | Graphics hardware and driver behavior |
| Profile-specific extensions and preferences | Browser engine and application version |
The browser determines which settings are stored per profile and which apply to the entire application. Sync accounts, imported profiles and product-specific sharing features can copy data across workspaces. Review those features when the separation matters.
Why two separate profiles can still look similar
Different storage does not require different rendering output.
Profile A and Profile B can each stay signed in to a different account while returning the same Canvas result on the same computer. That combination can be normal: the sessions are separate, but the rendering stack is shared.
Conversely, different fingerprint values do not prove that cookies are isolated. A test should inspect the relevant storage boundary directly rather than use a graphics hash as a substitute.
How to check the boundary you need
Use a harmless test value and the same test origin in each profile.
- Create two independent profiles and label their windows.
- On a test page you control, write a non-sensitive cookie or local-storage marker in Profile A.
- Open the same origin in Profile B and check that the marker is absent.
- Close and reopen Profile A to check persistence, then remove the test marker.
Use separate checks for each storage mechanism you care about. A cookie result establishes the cookie behavior tested; IndexedDB, extensions and synchronization have their own behavior. For real accounts, confirm the displayed account name without copying session tokens.
Why the distinction improves testing
Storage separation and fingerprint configuration solve different problems. A useful review rates them separately and describes the exact storage mechanisms, devices and restart conditions examined.
Interpreting the result
- A matching Canvas value does not establish shared cookies.
- A different public IP does not establish separate browser storage.
- Profile isolation and protection against another local user require different controls.
Frequently asked questions
Can two profiles use the same IP address?
Yes. Profiles normally share the available connection unless routing is configured separately.
Do extensions carry over to a new profile?
Extensions are commonly configured per profile, but sync, enterprise policies or a profile manager can install them across several profiles.
Is a browser profile the same as a virtual machine?
No. A virtual machine provides a separate guest operating-system environment. A browser profile primarily separates browser data and preferences.
References
Next steps
Organize separate account workspaces