How I built a Power Apps formula bar extension for Edge

If you’ve ever written a long Power FX expression in a Canvas app, you’ve probably run into this: you expand the formula bar so you can see what you’re doing—and it covers the canvas. You want to tweak something and instantly see the result? Tough. Collapse, check, re-expand. Repeat.

It’s been a long-standing gripe in the Power Apps community, and eventually, I decided to do something about it.

💡 Where the idea came from

The “I need to fix this” moment came in the Vantage365 office. One of my colleagues was debugging a complex gallery filter. We’d make a change, collapse the bar, check the canvas, re-expand. Rinse and repeat. We both complained out loud—again.

And I realised: I’d heard this complaint so many times from community members in The Power Apps Challenge Discord. I’d also grumbled about it myself more than once.

So I just said to myself: I’m fixing this.

🛠️ Starting from zero

I knew I wanted to build something lightweight, so I figured: why not try making an Edge extension? I’d used JavaScript and HTML before—Power Pages, web resource scripts—so that part didn’t scare me.

But I had no idea how extensions actually worked.

The first thing I Googled was:

“How do you make an extension for Edge?”

Turns out, most Edge extensions follow the same model as Chrome ones. So I started poking around some guides and realised I’d need a manifest.json file. What goes in that file though?

That question led me to the Microsoft Edge documentation on extension manifests, which was the first big piece of the puzzle.

The manifest.json file is basically the heart of the extension—it tells the browser what your extension is, where to find your scripts, what permissions it needs, and what sites it should run on. Mine defines things like:

Which script runs on what page (content scripts)
What permissions it needs to access the Power Apps Studio
The action that injects the button into the formula bar

I didn’t know any of this before I started, but after digging through that documentation and looking at a few sample projects, I had the basics in place.

🔍 The hardest part wasn’t the code

The core functionality of the extension is pretty simple:
It injects a pin/unpin button directly into the formula bar div inside the Power Apps Studio. When pinned, the formula bar shifts to the right side of the screen and switches from its usual horizontal layout to a vertical format—giving you full visibility of both your formula and the canvas at the same time. It also becomes resizable when in that pinned state.

Sounds straightforward, right?

Except the hardest part by far was figuring out the DOM structure of the editor. The Canvas Studio’s element tree is dynamic—elements and class names appear and disappear depending on what’s loaded and what’s in focus. I spent hours trying to identify:

The class for the full formula bar
The intellisense dropdown
The error message containers

The worst of them was the intellisense. Any time I clicked out of the formula bar to inspect the element, it vanished from the DOM. I spent far too long combing through the DOM manually, trying to figure out what was what. Eventually, with enough trial, error, and staring at class names, I got there.

✨ What it actually does

It’s simple on purpose:

You can resize the formula bar.
You can pin it to the right side of the screen.
That’s it.

This is my first extension, so I wanted to keep the scope tight and manageable. No sync features, no theming, no stored preferences—just something small that solves a common frustration.

🚀 Where to find it

The extension’s called PowerPin – Formula Bar, and it’s available:

On the Microsoft Edge Add-ons store
And publicly on GitHub

🧠 What I learned

Use Dev Tools constantly. Seriously. You’ll spend more time inspecting elements than writing code.
Narrow your extension’s permissions. If you don’t need access to every site, don’t ask for it. Keep it scoped.
Start small. I focused on doing one thing well, and that helped me avoid scope creep or overwhelming complexity.

✅ Final thoughts

This started as a personal itch. A small one, maybe—but one that lots of Power Platform makers share. And if you’re in that space and thinking about building your own tools: you don’t need to be a full-stack dev or an extension expert. Just find a problem worth fixing, and get stuck in.