Signed into work and personal Google in one window, the browser quietly treats one as /u/0, and work links start opening as your personal address. Give each account a session where it is the only account, and there is no default left to get wrong.
Containers for Chrome, in practice: each tab carries its own session, so two accounts on one site never see each other.
Keep both signed in without the /u/0 wrong-account trap.
Test a site as admin, user and guest at the same time.
If your SessionBox extension stopped working, here is how this one differs.
Moving from SessionBoxAn extension that touches every site you put in a session should be checkable. These are the commitments, and each one can be verified.
Read the sourceThe free extension is GPL-3.0 and public. The code this site describes is the code that ships: github.com/Envxsion/nvx_session.
Everything it runs is inside the package. It never downloads code to run later, so what the Web Store reviews is what runs in your browser.
There is nothing to sign up for. The free extension needs no account at all, and Pro is a licence key you paste in, not a login.
Popular extensions get offers from buyers who then ship tracking or ads in an update. This one will never change hands.
No browsing data. The full list of network calls:
Five alternatives, checked against their published plans and their own documentation. Every row below is included free in NVX Session; the marks show which of the others charge for it, do it partly, or do not do it.
25/25
NVX Session covers every capability below, free. The closest alternative, Firefox Containers, fully covers 13. On 11 of them, none of the five has it in full.
| Capability | NVX Session25/25 | Firefox Containers13/25 | SessionBox3/25 | Ghost Browser4/25 | Multi-profile browsers4/25 | Chrome profiles6/25 |
|---|---|---|---|---|---|---|
| How it separates accounts5 | ||||||
| The mechanism decides everything downstream. Swapping a shared cookie jar has a window where requests are already in flight under the old identity; rewriting the request does not. | ||||||
| MechanismAhead of 1 of 5 | Yes (Yes, included)Rewrites the outgoing Cookie header per tab. The browser jar is bypassed, never swapped | Yes (Yes)Origin attributes inside the storage engine | Partly (Partly)Swaps the one real cookie jar per tab | Yes (Yes)A separate Chromium profile per identity | Yes (Yes)A patched browser instance per profile | Yes (Yes)An OS-level browser profile |
| Many tabs loading at onceAhead of 1 of 5 | Yes (Yes, included)Rules are matched in C++ per request, so every tab is correct simultaneously | Yes (Yes)Engine level | No (No)A swap can only be right for one tab at a time; background tabs desync | Yes (Yes)Separate profiles | Yes (Yes)Separate instances | Yes (Yes)Separate profiles |
| Leaves your real cookie jar untouchedAhead of 1 of 5 | Yes (Yes, included)Cookies are copied into a private vault, never moved or deleted | Yes (Yes)Separate storage | No (No)Writes into the real profile jar | Yes (Yes)Separate profile | Yes (Yes)Separate profile | Yes (Yes)Separate profile |
| localStorage and sessionStorageAhead of 1 of 5 | Yes (Yes, included)Virtualised per session by a content-script shim | Yes (Yes)Partitioned by origin attributes | No (No)Shared across sessions | Yes (Yes)Profile level | Yes (Yes)Profile level | Yes (Yes)Profile level |
| Half-finished sign-in protectionAhead of 1 of 5 | Yes (Yes, included)A loop detector releases the site, because a partial cookie set reads as a hijack | n/a (Not applicable)No swap to go wrong | No (No)None | n/a (Not applicable) | n/a (Not applicable) | n/a (Not applicable) |
| What it costs you to run5 | ||||||
| An identity in a multi-profile browser is a whole browser process. Here it is a tab. | ||||||
| Memory per identityAhead of 3 of 5 | Yes (Yes, included)About 0 MB. It is a rule, not a process | Yes (Yes)About 0 MB | Yes (Yes)Low | Partly (Partly)Moderate | No (No)300 to 800 MB, per profile | No (No)About 250 MB, per profile |
| Cost of adding one more identityAhead of 3 of 5 | Yes (Yes, included)A tab | Yes (Yes)A tab | Yes (Yes)A tab | Partly (Partly)A profile | No (No)A whole browser instance | No (No)A window and a profile |
| How many at onceAhead of 4 of 5 | Yes (Yes, included)Hundreds. Measured, bounded by a 5,000 rule budget | Yes (Yes)High | Partly (Partly)Moderate | Partly (Partly)Bounded by memory | No (No)Bounded by memory, expensively | No (No)Bounded by memory |
| Stays in the browser you already useAhead of 4 of 5 | Yes (Yes, included)Chrome, Edge, Brave, Vivaldi, Arc, Opera GX | Partly (Partly)Only if you already live in Firefox | Yes (Yes)Chromium | No (No)A different browser | No (No)A different browser | Partly (Partly)Separate windows |
| Opera GXAhead of 4 of 5 | Yes (Yes, included)A first-class target with its own MV2 backend. Nobody else does this | No (No) | No (No) | No (No) | No (No) | n/a (Not applicable) |
| Whether you can trust it3 | ||||||
| Isolating cookies on every site needs access to every site, so the permission list cannot be the proof. What can be checked is the code, which is open source: no remote code, no account, and a short, published list of what it sends. | ||||||
| Keeps your browsing data on your machineAhead of 4 of 5 | Yes (Yes, included)Yes. Network calls are opt-in stats, cookie-free favicon fetches, and with Pro the licence check and opt-in encrypted sync | Yes (Yes)Yes | No (No)Cloud profiles are stored on its servers | Partly (Partly)Local | No (No)Cloud connected by design | Partly (Partly)Unless browser sync is on |
| Analytics you can read in fullAhead of 4 of 5 | Yes (Yes, included)Opt in, anonymous, a closed allowlist with no free-form field, erasable | Yes (Yes)None collected | No (No)Vendor defined | No (No)Vendor defined | No (No)Vendor defined | Partly (Partly)Browser vendor |
| States its own limits in publicAhead of 3 of 5 | Yes (Yes, included)Named on this page and on the Pro page, including the ones it loses | n/a (Not applicable) | No (No) | No (No) | No (No) | n/a (Not applicable) |
| Living with it every day6 | ||||||
| The parts you touch constantly, which is usually what decides whether a tool survives a week. | ||||||
| Tabs coloured by identityAhead of 3 of 5 | Yes (Yes, included)Per session, at a glance | Yes (Yes)Container colours | Partly (Partly) | Partly (Partly) | n/a (Not applicable)One identity per window | No (No) |
| Move several tabs at once, and undo itAhead of 4 of 5 | Yes (Yes, included)One guarded operation, so nothing leaks mid-move | No (No) | No (No) | No (No) | n/a (Not applicable) | No (No) |
| Keyboard shortcut to move a tabAhead of 4 of 5 | Yes (Yes, included)Alt and 1 to 3 | No (No) | No (No) | No (No) | n/a (Not applicable) | No (No) |
| Right-click a link into an identityAhead of 3 of 5 | Yes (Yes, included) | Yes (Yes)Open in container | Partly (Partly) | No (No) | n/a (Not applicable) | No (No) |
| Tells you which account a site thinks is defaultAhead of 4 of 5 | Yes (Yes, included)The whole reason the product exists | No (No) | No (No) | No (No) | n/a (Not applicable) | No (No) |
| Turn it off without uninstallingAhead of 1 of 5 | Yes (Yes, included)One switch, behaves exactly as if it were not installed | n/a (Not applicable) | No (No) | n/a (Not applicable) | n/a (Not applicable) | n/a (Not applicable) |
| Fingerprinting, and what it costs to get it4 | ||||||
| This is the row where the money usually is. SessionBox puts fingerprint protection on its $21.99 a month plan. Multi-profile browsers are subscription-only and start higher. Here Mirror and Standardize are free, and Persona is part of Pro. | ||||||
| Fingerprint control at allOnly NVX | Yes (Yes, included)Mirror and Standardize free, no account, no limit. Persona is Pro | No (No)None. Containers separate storage, not identity | Paid (Only on a paid plan)Professional plan, $21.99 a month | Partly (Partly)Minimal | Paid (Only on a paid plan)Subscription only, the deepest available | No (No)None |
| Checks the disguise is coherentAhead of 3 of 5 | Yes (Yes, included)A consistency validator. Incoherence is what flags you, not similarity | n/a (Not applicable) | No (No)Lets you build a machine that contradicts itself | No (No) | Partly (Partly)Vendor managed, not shown to you | n/a (Not applicable) |
| A default that fabricates nothingAhead of 3 of 5 | Yes (Yes, included)Mirror ships as the default: real fingerprint, only storage partitioned | n/a (Not applicable) | No (No) | No (No) | No (No)Fabrication is the product | n/a (Not applicable) |
| Tells you what each setting costs your detectabilityAhead of 4 of 5 | Yes (Yes, included)A generated manual inside the extension | No (No)Docs only | No (No)Docs only | No (No)Docs only | Partly (Partly)Partly | n/a (Not applicable) |
| Price2 | ||||||
| Unlimited sessions, free, is the shipped product. Nothing here is metered on how many accounts you have. | ||||||
| Cost to use it properlyAhead of 3 of 5 | Yes (Yes, included)Free. Unlimited sessions, with Mirror and Standardize included | Yes (Yes)Free | Paid (Only on a paid plan)Free tier is local profiles only. $4.99 to $44.99 a month | Paid (Only on a paid plan)Limited free, then subscription | Paid (Only on a paid plan)Subscription only, the most expensive category | Yes (Yes)Free |
| Metered on how many identities you haveAhead of 3 of 5 | Yes (Yes, included)No, and it never will be | Yes (Yes)No | No (No)Yes, cloud profiles are capped by plan | No (No)Yes | No (No)Yes, this is the pricing model | Yes (Yes)No |
The mechanism decides everything downstream. Swapping a shared cookie jar has a window where requests are already in flight under the old identity; rewriting the request does not.
An identity in a multi-profile browser is a whole browser process. Here it is a tab.
Isolating cookies on every site needs access to every site, so the permission list cannot be the proof. What can be checked is the code, which is open source: no remote code, no account, and a short, published list of what it sends.
The parts you touch constantly, which is usually what decides whether a tool survives a week.
This is the row where the money usually is. SessionBox puts fingerprint protection on its $21.99 a month plan. Multi-profile browsers are subscription-only and start higher. Here Mirror and Standardize are free, and Persona is part of Pro.
Unlimited sessions, free, is the shipped product. Nothing here is metered on how many accounts you have.
Competitor capabilities from their own documentation, pricing from published plans, August 2026. NVX Session has real limits too, and they are named on this page rather than hidden: see the questions below and the Pro page.
A browser keeps one cookie jar per profile, and a site can only treat one account in it as the default. Every link you open resolves against that choice, which is how a work document ends up opening as your personal address without anything warning you.
Every tab resolves to whichever account is default. The work doc opens as personal.
Each tab resolves to its own account. There is no default left to get wrong.
Each tab gets its own cookie jar.
Put an account in a session by signing in there, so it is the only account and therefore the default.
Switch accounts by switching sessions.
Throughout, cookies are copied, never moved. Nothing is deleted. The browser's own jar is left exactly as it was, so the worst case is that you turn the extension off and everything is where you left it.
Each one states the plain version first. Open any of them for the architecture.
Identity is rewritten at the network layer, not by swapping cookies.
Every move is one guarded operation.
MV3 can stop the extension at any moment. Sessions come back correct.
localStorage and sessionStorage are virtualised per session, and the rest is disclosed.
It notices when a login is looping and stops fighting the site.
One bad session cannot spend the whole rule budget.
MV3 for Chromium, a blocking backend for Opera GX.
Set per session. Mirror and Standardize are free; Persona is Pro.
No browsing data leaves your machine. Usage stats are off until you switch them on, two independent gates hold them shut, and what they can carry is a closed list with no free-form field in it.
Opt in, anonymous, and built so it cannot carry anything.
No fingerprinting vectors, even in the analytics.
Which is usually what decides whether a tool survives a week. Hover or focus any of them to see it work.
Every tab wears its session colour, so you can see which account you are in without clicking anything.
Select several tabs and move them together. It runs as one guarded operation, and undo puts them back.
Alt and a number sends the current tab to that session. No menu, no dragging.
Open any link or page directly in the session it belongs to, from the context menu.
It tells you which account a site is treating as default, which is the thing nothing else surfaces.
Turn it off and the browser behaves exactly as if the extension were not installed. Nothing is lost.
The short answers. The help pages have the long ones.
No. It separates cookies per tab. Your network connection is unchanged, your IP is the same in every session, and nothing is routed anywhere.
It can, in one specific case. If a sign-in ends up half finished, a federated provider like Google can read that as a hijacked session and invalidate it everywhere. That is why signing in fresh inside a session is the recommended path, and why a loop detector releases a site rather than retrying into that outcome. Cookies are copied and never moved, so your original session stays intact.
Yes. It is domain agnostic and does not special-case any provider. For federated logins, sign in fresh inside the session rather than importing an existing one.
Yes, with unlimited sessions. A Pro tier is planned later for deeper isolation, and it will never meter how many sessions you can have.
Nothing unless you opt in, and then only anonymous, bucketed counts from a closed allowlist. The full list is on the telemetry page.
Profiles cost a window and about 250 MB each. Containers are deeper but Firefox only. This is the closest thing to Containers for Chrome: per-tab sessions, in the browser you already use, at roughly no memory per session. Firefox Containers still isolate more, including the cache.
Yes. Put each role in its own session, for example admin, user and guest, and keep the tabs side by side. Each tab sends only its own session's cookies, so the roles do not mix.
It does the same core job, multiple accounts on the same site in one window, with a different mechanism and a few differences worth knowing first. They are set out on the page for SessionBox users.
Free, unlimited sessions, and it stays in the browser you already use.