I Built a macOS App to Stop Links From Opening in the Wrong Chrome Profile

#productivity #opensource #automation #showdev

I use multiple Chrome profiles.

Every morning I open Slack, click a Notion link, and watch it open in my personal profile. I copy the URL, switch to the work profile, paste, hit enter. Then I click a GitHub link in email — same thing, wrong profile. Copy, switch, paste.

I've been doing this dozens of times a day for years. At some point I stopped counting and started building.

What I Wanted

Route links from outside Chrome (Slack, email) and links clicked inside Chrome
Set a rule once and forget about it — no profile picker every time
Support wildcards and regex, not just exact domains

I wanted something that covered the full loop. So I decided to build it myself.

So I Built It

LinkPrism is a macOS menu bar app. You set it as your default browser, add a few rules, and that's it.

notion.so        → Work
github.com       → Personal
*.atlassian.net  → Work
docs.google.com  → Ask every time

Rules can be exact host matches, wildcards, or regex. For domains you use across profiles, there's an "Ask" mode — a profile picker pops up and you can check "Don't ask again for this URL."

This handles links from Slack, email, Telegram — anything outside Chrome. But there's a catch.

The Harder Part: Links Inside Chrome

Links clicked inside Chrome never hit the OS default browser handler. Chrome handles them internally. The app can't see them.

So I built a companion Chrome extension (Manifest V3) that:

Syncs rules from the macOS app via a local HTTP server on 127.0.0.1:19384
Detects which Chrome profile it's running in using chrome.identity
Matches rules client-side on every navigation
Reroutes only when the current profile is wrong — no unnecessary redirects

Now the full loop is closed. External links go through the app. In-browser links go through the extension. No gaps.

The Thing I Didn't Expect

After using it for a while, I realized the annoyance wasn't just the extra clicks. It was the context switching. Every wrong-profile link pulled me out of whatever I was focused on. Fixing this tiny friction removed a surprising amount of daily cognitive noise.

If you juggle Chrome profiles, you might not even notice how much energy goes into this routine until it's gone.