why are image thumbnails not displaying in finder since updating to sequoia on my m1 MacBook pro

Same here - jpegs and pngs. What I've tried is opening the image in Photoshop and then saving it as a copy. The new version shows the preview icon and then I delete the one that doesn't. It's not ideal but it seems to work and all of the metadata is preserved.

I am running 15.0.1. I am having the same issue mostly with PNG files and some Jpeg. I confirmed that it is not the file by copying it to a different older Macbook not running 13.4.1 without issue. Moving file to new location on the same computer does not resolve issue. Quick Actions/Convert Image creates a new file that shows thumbnail. Very frustrating.

I doubt it is as much as Apple blocking third-party Quick Look code as the software may not have been recompiled to work with the current operating system and any Apple Frameworks that may have changed since the third-party plug-in was originally released. That is on the developer, not Apple.

I used to have a Markdown QL engine that was written several years ago that has not been updated or worked since macOS Big Sur because the original developer never stayed engaged with keeping it current.

In that Finder Window that you just provided a screenshot, press cmd+J to open the Show View Options panel. Is the Show icon preview selected, and if not, by selecting it do the generic icons change to their respective image?

When those PNGs were produced, was there an option to include an icon image that may have been overlooked?

I wish to add here, all of my software produce files that no longer have thumbnails. I have Moho pro 14, Corel Painter, Rhino 7, and CorelDraw that now no longer show thumbnails for their native files within Finder after migrating to a new Mac with OS Seqouia. That would be formats: 3dm, Moho, CDR and RIFF. Hope this helps, thanks in advance

I just updated to Sequoia also. Half of my thumbnails (PNG and JPEG) images are no longer showing. If I click one, it does show the image in the preview sidebar. Relaunching finder did not work either.

These files are not in an isolated location. They're everywhere from the downloads, documents, and other folders. They are NOT on my external drives. So it's definitely system based.

My fix: Open in Preview > Save file. Thumbnail shows up again.

Definitely needs a fix!

Can you me a bit more specific about what you are not seeing? Are we talking about the images that Finder displays for different parts of you Mac, like Applications, Documents, Desktop?

Clicking on one image and Get Info and see what "Open With" shows. On mine it shows Preview.

This is probably the only way. But I have a lot of files in different folders, and it's not very convenient to convert. I hoped there would be a fix in 15.0.1, but nothing has changed. Thanks anyway!

You mean they actually blocked third party thumbnail previews on purpose? What would be the rationale, if any? Safety?

This is usually a preferences updating problem.

Try deleting the com.apple.finder.plist and relaunching the the finder.

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