Chrome containers: what isolates accounts

Chrome containers are what people often want when they need a work and personal login open on the same site. Chrome Help documents separate profiles, not a built-in Firefox-style container tab feature. Its built-in separation option is profiles; extensions make narrower claims about per-tab sessions. (Google Chrome Help (2026 check))

The useful question is not whether an option calls itself a container. It is which browser data it separates, and whether two identities can stay visible in the same window. The comparison below uses vendor documentation and marks gaps as “not documented.” Checked October 2026.

Do Chrome containers exist as tabs?

Chrome documents separate profiles, not native Chrome container tabs. To keep two accounts signed in at one site, use multiple Chrome profiles: make one for each identity and open the site in each profile.

In Chrome, select Profile at the top right, then Add Chrome profile. Name one profile Work and another Personal. Sign into the site separately in each. Google sign-in to the browser is optional; if you turn on Chrome sign-in, Google says bookmarks, passwords and settings can be saved to that account and used on other devices. Those steps and labels were checked October 2026 in Google Chrome Help (2026 check).

The cost is workflow: you switch between profile contexts instead of picking a container for each tab in one shared strip. Google’s Help describes profile switching; it doesn’t document a way to mix profiles inside one window. If you want identities as tabs, Firefox lets you assign each new tab to an identity, while a Chrome extension is a separate option to review (Mozilla MDN (2026 check)).

What does each option isolate?

Chrome and Safari describe profile-level separation; Mozilla lists exactly what Firefox containers separate; the Chrome extension listing below makes a cookie claim. A blank cell would hide those differences, so “not documented” or “not itemized” means the source doesn’t name that data type.

Option	Cookies	localStorage / IndexedDB	Cache	History	Extensions	Same-window account tabs?	Source
Chrome profiles	Separate: each profile directory holds its own cookies	Not itemized	Not itemized	Separate by profile	Not itemized	Not documented as mixed-profile tabs	Chromium docs (2026 check) and Google Chrome Help (2026 check)
Safari profiles	Separate	Website data separate; specific APIs not itemized	Not documented	Separate	Available across profiles; enabled separately	No mixed-profile tabs documented; switch from a start or empty page	Apple Support (2025; checked 2026)
Firefox Multi-Account Containers	Separate	Separate	Separate (HTTP and image cache)	Shared (not yet separated)	Not documented	Yes: each tab is assigned an identity	Mozilla’s Containers notes (2026 check) and Mozilla MDN (2026 check)
Chrome “Multi-Session” extension	Separate cookies, according to its listing	Not documented	Not documented	Not documented	Not documented	Yes, per its listing	Chrome Web Store listing (updated September 2026)
Octoweb workspaces	Separate	localStorage separate; IndexedDB not documented	Separate	Separate	Not documented	Not documented	Octoweb workspace overview

Chromium’s docs say each profile is its own directory holding data such as history, bookmarks and cookies; Chrome Help says profiles keep bookmarks, history, passwords and other settings separate. Neither itemizes web storage, cache or extensions. Apple calls cookies and other “website data” separate, but doesn’t itemize IndexedDB or cache on this page. Apple also says Safari extensions are available across profiles and can be enabled separately. That’s a narrower claim than separate extension installations. See Chromium’s user data directory docs and Apple Support’s profile details (2025).

Mozilla is unusually specific about Firefox containers. Its implementation notes say cookies, localStorage, IndexedDB, the HTTP data cache and the image cache are separated per container; history and bookmarks aren’t separated yet; saved passwords and saved search and form data are shared on purpose. See Mozilla’s Containers notes (2026 check) and the contextual identities reference (2026 check).

Are Chrome container extensions enough?

Some Chrome Web Store extensions claim same-window cookie isolation, the closest thing to multi-account containers in Chrome, but a listing isn’t a technical audit. For example, Multi-Session: Multi Login Manager says each session tab has its own cookie jar and that cookies do not cross sessions. Its listing says version 1.0.3 was updated September 29, 2026, and discloses that it handles authentication information. The listing doesn’t spell out localStorage, IndexedDB, cache or history separation, and it doesn’t show a requested API permission list. Those are the listing’s claims, checked October 2026 — not independently verified behavior. (Chrome Web Store listing (2026))

Before installing one, read the permission prompt at install or update. Google says access to data on all websites lets an extension read, request or modify data from every page you visit. If the extension asks for broad access, decide whether that scope makes sense for a tool that manages sign-in sessions; decline if it doesn’t. See Chrome Web Store’s permission guide (2026 check).

Use the extension route only if its stated boundary is enough for your job. If your requirement includes IndexedDB or browser cache separation, this listing doesn’t document that. If you want Mozilla’s maintained container system, its Firefox Multi-Account Containers help (2026 check) explains multiple accounts on one site, assigning sites to containers and its toolbar workflow.

Which option fits Chrome or Safari on a Mac?

Pick by the boundary you need:

• Stay in Chrome and separate more than logins: use Chrome profiles. You get distinct profile data and need to switch profile contexts. The current Chrome profile steps are Profile → Add Chrome profile, checked October 2026.
• Stay in Chrome and keep accounts in one window: a session extension may fit if its documented cookie boundary and permissions are acceptable. Don’t assume its tabs separate other stores unless its own documentation names them.
• Use Safari on a Mac: Apple’s profile guide covers Safari 17 or later and says Safari → Create Profile or Safari → Settings → Profiles; the macOS 27 Safari guide documents Safari → Settings → Profiles, checked October 2026. New profiles keep browsing history, cookies and website data separate, and extensions can be enabled per profile. Apple says Passwords and AutoFill information are shared between profiles, so Safari profiles aren’t a way to separate saved passwords. (Apple Support’s Safari profile guide (2025; checked October 2026))
• Keep identities as tabs with documented storage boundaries: Firefox containers do that. Add Mozilla’s Multi-Account Containers extension if you want its site assignments and controls. Mozilla says containers are disabled in Private Browsing windows (Mozilla Support (2026 check)).
• Use separate Mac browser workspaces: I build Octoweb, so weigh that accordingly. Its workspaces each have their own tabs, history and WebKit data store; cookies, localStorage and cache don’t leak across workspaces, and two accounts can stay signed in to the same site. Moving a tab with ⌘⇧M reloads it in the destination workspace; its live page and back/forward history don’t come along. IndexedDB separation and same-window behavior are not on record, so I wouldn’t treat them as guarantees. (Octoweb’s workspace overview)

If another person can use your unlocked Mac, a browser profile is not a device lock: Google Chrome Help (2026 check) warns that someone with the device can switch to another Chrome profile. For the difference between profile separation and a private session, read what private browsing does and does not separate.