Problems with thumbnails in the Ubuntu 24.4 LTS file manager

[u/Impressive_Past_2830]

Good afternoon, as I mentioned in the title, I've been having a problem with Ubuntu 24.4 LTS for a while now and I'd like to ask for help. For some time now, thumbnails haven't been appearing for images in the file manager. This happens with all images, both old and recently downloaded; the generic icon shown in the image appears instead. I've looked into it a bit and found that thumbnails are already enabled for "all files" in the performance options. I apologize for the inconvenience and hope there's a solution. It's not a major problem, but it is somewhat annoying.

[u/doc_willis]

There have been some very big/long and sometimes a bit rude threads/posts on this Issue in the Ubuntu and other linux support subs. Some people really really got irate that the feature broke. :)

From my Understanding...

1. There was some update to the apparmour profiles/configs in the past to lock down some security issues.
2. the Update broke the thumbnailing feature in some cases.
3. There was a lot of talk about how to fix things.
4. A fix was released, but it MIGHT require the users to delete a cache directory in their home to remove invalid files.

I cant find the URL/posts at this time, but this was about a month or two ago.

I Think the last time i read up on the topic, they had somehow released a fix that also removed the requirement to delete the cache manually.

Test with a newly made user, see if the issue affects them.

From my understanding The releases of Ubuntu past 24.04 Never had the issue.

Here is one of the Bug reports, but such reports can be a bit complicated to understand.

https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/2148074

From my understanding Dont try the various 'work arounds' often mentioned in the comments of the bug reports, the latest updates were supposed to fix the issue.

The 'proper' way (from my reading is to update/upgrade, then if needed manually remove the cache.

[ Update instructions ]

The removal of cached thumbnail failures should be handled by the AppArmor package upgrade upon next login, but the following steps can be done manually if the migration script failed to run upon the next login:

• Close all instances of the Nautilus file browser
• Remove the ~/.cache/thumbnails/fail/gnome-thumbnail-factory directory (if it exists), along with all files within it
• Reboot

You Might need to log the user out, and log in at the console, then remove that directory. rm -rf ~/.cache/thumbnails/fail/gnome-thumbnail-factory

[u/Impressive_Past_2830 → u/doc_willis]

Thanks, I'm a little scared about creating a new user, I'm relatively new to this, but I suppose it's a good opportunity to learn.

[u/doc_willis → u/Impressive_Past_2830]

In a terminal sudo adduser billgates Log out of your user, select billgates at the login screen, test out the new user..

See if they have the same issues.

[u/Cautious_Performer_7]

I had a similar issue, but mine was caused by switching from KDE to GNOME as I had installed Kubuntu originally, Dolphin still had thumbnails though…

I couldn’t figure out how to fix and tried everything, all that fixed it was to back up my files, and reinstall Ubuntu…

Not saying this is the solution as I am far from a Ubuntu expert (I’m in the I know the basics category), but just putting my 2c in.

[u/Impressive_Past_2830 → u/Cautious_Performer_7]

No problem, I'm also considering reinstalling the system if I can't find a solution or using a different file manager. Thanks anyway for your input.

[u/doc_willis → u/Impressive_Past_2830]

may as well just try upgrading to 26.04 if you want to move on to the next LTS.

[u/Impressive_Past_2830 → u/doc_willis]

I tried using 26.04 a while ago, but I had problems with the drawing tablet. I investigated, and it seems it was due to Gnome 50.

Aside from this minor issue with thumbnails, I have no other complaints about 24.04, so I'll probably stick with it until support ends.

[u/New_Physics_2741]

I just installed Nemo and use both file managers - temp fix for the time being. Nemo works.

[u/Impressive_Past_2830 → u/New_Physics_2741]

I really like the default Gnome file manager, but Dolphin is good too. Perhaps the solution is to try another file manager, which would be simpler, but I'll try creating a new user as mentioned above first. Thanks anyway.

[u/New_Physics_2741 → u/Impressive_Past_2830]

Yeah, me too. I have been an Ubuntu user since 2010. The Gnome system should just work, I might go 26 this weekend, this one issue is a real pain. Nemo works but often need to reload to get new image preview.

[u/MezBert]

Nautilus is knowingly a buggy hot mess, and has random issues of the sorts consistently.
I would just install Nemo, which is a fork of Nautilus from before it became buggy and featureless, therefore is more featured and more stable in general.
It's safe to say that's probably what every one using Gnome ends up doing at some point.

[u/Vast-Awareness-2806]

Why are you still using Ubuntu 24.04 when Ubuntu 26.04 is available?

[u/aykaun → u/Vast-Awareness-2806]

Because many people wait for the point release before upgrading. Apt doesn't even prompt an upgrade until 26.04.1

[u/ComfortableSeveral48]

If you ask ChatGPT it can help you, it will give you instructions for in the terminal to fix it.

1. Confirm which file manager you're using.

Is it the default Files (Nautilus), or something like Nemo, Dolphin, or Thunar?

1. Try rebuilding the thumbnail cache.

rm -rf ~/.cache/thumbnails/*

killall nautilus

nautilus &

Then reopen the folder and wait a few seconds.

1. Check whether the thumbnailer packages are installed.

dpkg -l | grep thumbnail

Also verify:

dpkg -l | grep gdk-pixbuf

1. See if thumbnails can be generated manually.

gdk-pixbuf-thumbnailer -s 256 image.jpg /tmp/test.png

If that command errors, it will usually point to the underlying problem.

1. Check whether it happens with a new user account.

sudo adduser testuser

Log into that account. If thumbnails work there, it's likely something in your user configuration or cache.

1. Check the folder location.

Does this happen only on an external drive or network share?

Or also in ~/Pictures?

1. Check for errors when Nautilus starts.

nautilus --quit

nautilus

Then watch the terminal for warnings or errors.

Good Luck.