Configurable Containers — Arlo

Configurable Containers decides which Firefox container each site opens in, from one YAML file you edit as text.

Write a rule for the sites you want a named container for. Everything else opens in a fresh throwaway, cleaned up once you close its tabs.

What it does

• A bare domain is the common case: it opens in a container named after it. Add detail for a different name, several domains in one container, or a choice between containers.
• Single sign-on keeps working: identity providers stay in the container the login started from, so "Sign in with Google / Microsoft / Okta" does not break.
• Sites you group together share one throwaway; an unrelated site gets a clean one.
• A rule can offer several containers and let you pick.
• Known link redirectors are not isolated, and the tab closes itself if it strands you on one.
• Optional per-site cookies and content scripts, applied in the routed container.
• Reopen the current tab in another container with Ctrl+Shift+O.

How you configure it

There is no settings screen — the YAML file is the whole interface. You edit it in the add-on's own editor (about:addons → Configurable Containers → Preferences). Saving checks the file and applies it at once; an invalid config is refused.

The shipped default routes nothing by name. It marks the few hosts where isolating would break something, and includes commented examples to start from.

Privacy

Nothing is collected and nothing is transmitted. Your configuration stays in your browser.

Source code and configuration reference: github.com/ArloL/configurable-containers