Hi everyone, I'm new to linux and the transition for the past month has been somewhat smooth with the exception of an issue that I cannot figure out. It's been extremely frustrating as I've tried self-searching online as well as asking others, but so far no success. Any help with debugging this would be GREATLY appreciated!

Current Setup:
OS: Linux Mint Cinnamon 20.1 x86_64
Kernel: 5.8.0
CPU: AMD Ryzen 7 PRO 4750U
Drive Space: 52 GB avail out of 1 TB
Memory: 3351MiB / 31396 MiB
File Manager: Nemo 4.8.6

Issue:

• Nemo stops auto-generating thumbnail previews when browsing through the file manager in "icon view", whether .jpg, .png, .gif, .pdf, .mp4, .mpeg, etc.
• The folder was transferred to my local drive from an external HDD
• The folder is about 600 GB with many photos, videos, and subfolders
• After a reboot, thumbnails will generate for ~30-40 files before stopping and will no longer auto-generate for the remainder of my session in the current directory or any other subfolders
• If I open each photo in Xviewer, close the file, go back to Nemo, navigate out of that photo's directory, and then navigate back into the photo's directory, a thumbnail for that photo will be generated
• IF HOWEVER, I hit CTRL + R, that thumbnail will immediately disappear

Attempted Solutions:

• Deleting .cache/thumbnails folder & reboot
• This results in the same issue where a thumbnail will only generate for ~30-40 files before stopping completely
• Adjusting the preference settings in Nemo

Screenshots of Issue:
https://1drv.ms/u/s!AklmBcOV4OARgstESu5GB-CJzhl05A
https://1drv.ms/u/s!AklmBcOV4OARgstFj4CZLpfLADBVlw
https://1drv.ms/u/s!AklmBcOV4OARgstGq7q25wU6CyjQcg

Apparently, this is not a new issue. A web search for "nemo linux thumbnails" turns up a number of articles.

This one from the Mint forums looks like a good place to start: https://forums.linuxmint.com/viewtopic.php?t=231128

I actually came across that post myself when trying to search for a solution. It seems like even for that post, it was abandoned by the OP with no real solution huh?

I also came across this older post today as well, and it seems like they also had no solution and that it's hypothesized that it's an issue with Linux Mint Cinnamon & Nemo. It seemed like the general consensus for the OP in that post was that he/she needed to look for another distro altogether.

If changing distros is my only solution (or if worth a shot), what beginner-friendly distro alternatives would you recommend that is as polished as LM? From my own searches, it seems like the good options would be Ubuntu LTS or Elementary OS?

Rather than changing distros, you could look at trying out different file managers. (Personally, I've never been a big fan of Nemo. And I agree with you that Mint is a polished distro. I tend to think of it as "Ubuntu done right".)

You might want to take a look at KDE's Dolphin; it should be in the Mint repos. I just opened a directory containing about 3,000 image files in Dolphin on Mageia v. 8 and it successfully loaded thumbnails for all of them.

Also, welcome to LQ.

Thank you for the welcome! And I very much appreciate your help with my problem.

I will definitely try KDE Dolphin. Also, sorry for the following questions as I'm still trying to make sure I understand the terminologies correctly:
1) Isn't KDE a desktop environment? Would I be able to run Dolphin file manager while still running Cinnamon as my DE?
2) When you refer to KDE's dolphin being in the Mint Repos, are you referring to this http://packages.linuxmint.com/ ?
3) Could I simply install Dolphin via this link appstream://org.kde.dolphin.desktop
4) Would I need to uninstall Nemo to prevent any issues of running two different file managers along side each other?

Dolphin is a KDE application, but you should be able to install it without any issues. Mint's package manager will install any required libraries, so you can run the application. Yes, KDE (Plasma) is a desktop environment, but you don't have to be using KDE to use Dolphin, so long as you have the required libraries in place.

I believe that Mint Cinnamon includes the Synaptic Package Manager. I think you will find it on the menu under "Administration." Otherwise, you can use the menu "search" to find it. (I'm basing this on my VM of Mint 19.3 Cinnamon.)

Open it and search for "dolphin." You will find a number of packages. Select the one simply named "dolphin" and described as "the default file manager for plasma."

As an aside: it is always best to install applications from a distro's own repos, rather than from external sources, since that ensures that all dependencies (libraries needed for the application to work properly) will be satisfied. You can install applications from other sources, certainly, but it can get complicated. (And that's a whole nother topic.)

Nemo allows you to choose to generate thumbnails on a per folder basis - or you can configure thumbnails by setting generation according to the parent folder setting.

In addition, you can use a toolbar icon to toggle thumbnails on/off.

Attached Thumbnails