How To Fix: Mac QuickLook Preview Is Not Working

When Mac shows a thumbnail instead of the full photo

Semih Aykut
4 min readNov 1, 2022


Mac spacebar preview shows a thumbnail instead of the photo or video. Screenshot by Semih Aykut (Author)

I’ve made an app to fix the Quicklook bug on MacOS. You can get it from

Here is the back story of this:

Ever since 1998 (I was in elementary school), this is the first time I‘m using a Mac again. In early 2022 I bought a new one.

After I got used to Cmd instead of Ctrl, quitting the app with Cmd + Q, and Activity Monitor instead of Ctrl + Alt + Del, I was all set.

It was interesting that, even after 24 years it looked familiar. I realized that the human brain saves the data well. Opening a file animation, Apple logo in the corner, rounded buttons, Finder logo, About menus... It’s the same feeling with fancy up to date technology. Made me remember the old times.

Got used to Mac real quick. Installed Xcode, started experimenting with Swift and Objective-C.

I had an experience in 2015 that I had used Objective-C while nobody around me even knew about it. I remember the syntax was a little bit harder than other languages. But I was able to make the macOS app I wanted back then, so I had the confidence now. I wanted to develop new things.

First I’ve made my game Numbrle’s iOS version with Swift.

Numbrle iOS version. Screenshot by Semih Aykut (author)

Swift’s syntax is way better than Obj-C. (No offense but still not appealing to the eye in my opinion.)

But it was easier compared to Obj-C. (You still need to use Obj-C sometimes. So you write a couple of functions when you really need.)

After Numbrle for iOS was released and I used the new Mac for 6 months for daily use, work, games, music, I realized that this “spacebar preview for photos and videos showing as the thumbnail” thing, was indeed a bug, not a feature 😂 .

First I thought this is the Mac’s way of showing photos. When a friend of mine said “Yes when it does like that, I restart the Mac and it shows correctly.” I was aware that something is wrong, but only sometimes.

Ideas started flowing. Photo by Per Lööv on Unsplash

The idea emerged in my mind. “Did anybody do anything about this? Is there a fix for this that’s not involved with writing terminal codes or restarting the computer or processes with Activity Monitor? Only if I could solve this. Maybe I can make an app for end users that are not super tech-savy.” I kept ignoring the idea for 2–3 months. While I encountered the bug all the time.

One day I made a google search. Tens of thousands of people searching about this. I saw youtube videos. 30k views on one. There are the solutions, but only for tech-savy people. Those who know their way around a computer when slightly technical skills are needed. From what I know, in real life, people like that are not that common.

I checked what they are searching for:

mac preview not working

quick look not working

how to fix quick look

quicklook showing thumbnail

spacebar preview doesn’t work

I got the motivation. As soon as I got the time, I started.

I finished. Named it Quick Look Fix. Made it a lightweight menu bar app. Started using it myself. Whenever the quicklook bug happens, I just clicked and kept working. Not restarting the Mac, not restarting the Finder. Not losing my open folders.

Fix Quick Look Now. That’s all. Screenshot by Semih Aykut (author)

Made the website. Polished the looks. Published it on

Started launching it on the internet.

Let’s not make this longer and let this be the end of Part 1.

If this article gets good reads, I’ll get that people are into this. So I’ll share more insights about the launch, receptions at the launch places, reactions, comments and maybe more.



Semih Aykut

Computer Science BSc. I like electric guitars, swimming and cats.