Open each client’s links in their own Firefox profile

Junction is a free, open-source macOS app that becomes your default browser and routes each link by your rules. With one rule per client, their links open in that client’s Firefox profile, with that client’s logins, cookies, and extensions.

How do I open a link in a specific Firefox profile?

Write a rule that matches the client’s sites and opens Firefox with that profile’s name. Junction launches Firefox with the profile however you clicked the link.

{
  "name": "Acme → Acme profile",
  "match": { "patterns": ["*.acme-corp.com/*"] },
  "action": { "app": "org.mozilla.firefox", "profile": "Acme" }
}

$ junction test "https://portal.acme-corp.com/tickets"
input:       https://portal.acme-corp.com/tickets
rule:        [1] Acme → Acme profile
action:      open in org.mozilla.firefox profile "Acme"
url:         https://portal.acme-corp.com/tickets

*.acme-corp.com/* matches every subdomain of acme-corp.com and the bare domain too, at any path.

What name does Firefox’s profile need?

Use the profile name exactly as firefox -P lists it. Junction also lists Firefox profiles under Settings → Browsers.

Listing profiles needs Full Disk Access, which Junction uses only to read Firefox’s profiles.ini. Unlike Chrome, a Firefox profile rule needs that access: without it, the link opens in your fallback browser instead.

How do I set up one profile per client?

Add one rule per client, each with that client’s domains and profile. Rules run top to bottom and the first match wins, so a client rule only needs to sit above any broader rule that would also match.

{
  "name": "Globex → Globex profile",
  "match": { "patterns": ["*.globex.io/*", "globex.atlassian.net/*"] },
  "action": { "app": "org.mozilla.firefox", "profile": "Globex" }
}

A client’s own Jira or Slack workspace usually has its own subdomain, so it can go in that client’s rule.

What happens if a profile is deleted?

The link still opens. If a rule names a Firefox profile that no longer exists, Junction opens the link in your fallback browser rather than dropping it or opening the wrong profile.

Can I use Firefox containers instead?

No. Containers are a Firefox extension feature with no launch option Junction could use. Firefox profiles are supported, and Chrome profiles work the same way — see Chrome profiles.

If you’d rather choose a profile per click than per rule, let the picker ask.

Get Junction

Junction is free and MIT-licensed, for macOS 13 or later on Apple silicon and Intel. Install it with Homebrew or the DMG, then follow the first-launch steps.