I asked my AI coding agent to build the one feature every website is missing, and now I press Space on every link

Every website I use is missing the same feature: a way to peek at a link without leaving the page. On my MacBook Air, I can tap Space on any file and see it instantly, and Windows has PowerToys Peek doing the same job. Links still get a new tab, a two-second look, and a guilty Cmd + W. I do that about twenty times a day.

So this Monday, I asked Claude, my AI coding agent of choice, to build that missing feature as a browser extension. Now I'm not a developer, but I ended up making this extension within a day. It's called ‘Quick Look’ for LINKS, and I've shared it for free.

How I described a link preview extension to Claude

One long message, and a plan before any code

My first message went out at around 10:30 p.m. on Monday, and it read more like a fan letter than a spec. Hover over any link, press Space, and get a frosted panel with the page inside. The arrow keys should flip to the next link the way they move through files, Option + Space should go full window, and Return should open it for real. Then came my safety list: nothing loads on hover, no cookies, no servers, and risky links refused. I signed off with "Go all in, without thinking about time passed and tokens used," which is a brave thing to type at night.

Claude replied with a plan before it wrote any code: four preview types (Live, Reader, Summary, and media for images, YouTube, and PDFs), a sealed frame for every preview, and a test plan. Then it built the thing: about 4,800 lines of its own code, plus Mozilla's Readability library for the Reader view. Just before midnight, version 1.0 was a zip file in my Documents folder. The current build is free on GitHub.

Can an AI coding agent find its own bugs?

Version 1.0 had a scary security hole

Claude had already tested it in its own copy of Chromium and fixed a pile of bugs before I saw anything. YouTube previews showed Error 153 until it added a referrer rule. On Wikipedia, the arrow keys flipped through only three links, because it grouped them too narrowly. A second Claude agent then reviewed the code for security and found that any website could embed the preview page and drive it. I would never have spotted that, mostly because I didn't know it was possible.

My own first bug report was less impressive. I installed it on my MacBook Air M2. Then I wrote, word for word, "i don't know if it opened or not, but when i take the pointer on learn more, and press spacebar, then it is opening." It was, in fact, opening. We did find a real one, though: after a preview opened, Claude's own browser tool lost control of that tab. At 12:33 a.m., version 1.0.1 started removing the preview frame 20 seconds after you close it.

Version 1.1 had to handle some broken sites

YouTube already owns the spacebar

The next afternoon, I used it like a normal person and sent one long message about the four sites that broke it.

YouTube already owns the Space bar, since it pauses videos and scrolls the feed. Now, Shift+Space previews links on every site, while plain Space stays with YouTube, Google Docs, Figma, and a few others.

WhatsApp Web showed "refused to connect" because WhatsApp only accepts frames that opt in. Claude now rebuilds the frame in a mode Chrome allows there, but only when the normal frame gets no answer. Its first attempt used that mode everywhere, which quietly broke the setting that lets chosen sites use your cookies, until the second review caught it.

On a store's account page, pressing Space on "Log out" just scrolled. If the extension can read where a button goes without running it, it previews that. Otherwise, a small bubble says "Log out" runs an action, so it won't be pressed. Sign-out, unsubscribe, delete, and one-time sign-in links are refused unless you pick Preview Anyway.

XDA pages always open in Reader because the site tells browsers not to show it inside other pages. The live page now loads by default inside the sealed, logged-out frame. Instagram then showed nothing but a sign-in wall, so social sites stay on the Summary card.

I ended that message with "do not ask me to check anything more," which Claude took remarkably well. Version 1.1 landed at 4:01 p.m.

Why few people would fail to install it

It's still an unpacked extension

For the public release, I renamed it ‘Quick Look’ for LINKS, and Claude found two more bugs while retesting. In about one in four runs, Space did nothing after a preview closed, because focus got stuck in the hidden frame. After an update, an old copy could show the hover hint twice. Both are fixed in version 1.2. When the GitHub connection refused to work, Claude uploaded everything through GitHub's website in my Chrome, ten commits and one release.

The catch is that it isn't in the Chrome Web Store. You install it with Developer mode and Load unpacked. If you pick "On every website," Chrome warns that it can read and change all your data, since previewing any link means reaching any site. A per-site mode avoids that. Pages behind a login show the logged-out version, because previews don't send cookies by default.

On Windows, the install steps are the same in Chrome or Edge. Use Ctrl where I use Cmd, or switch the shortcut to Ctrl + Space in settings to match PowerToys Peek.

I can't vouch for every line of that code. I can vouch for the tests, the two reviews, and the evenings I've spent pressing Space on everything since.

I still open tabs, just fewer throwaway ones

I didn't write this extension. I described it, broke it, and complained about it in lowercase until it worked, which turned out to be a real job. An AI coding agent is only as good as the bug reports you hand it, and mine got better by the second day.

I kept telling you the timeline, so you know that it was done in a day of heavy multitasking. I hope this inspires more people to streamline their work with AI.