Yep, shows thumbnails for pictures, videos, pdfs etc. More formats than Windows in fact. Windows has been standing still, the rest of the world hasn't.
I am using GNOME 40 and I just opened a file picker in Totem, the official video player. I did not find a way to switch the file picker from "Details" mode (one line per file, with size/type columns and a very very small thumbnail) to a "grid thumbnail" mode where they would be recognizable. The related bug is still open at https://gitlab.gnome.org/GNOME/gtk/-/issues/233, so I don't think this has been fixed.
The reason does not matter. It really is truly, absolutely irrelevant.
If Windows has issues with paths longer than 260 chars (only PARTIALLY fixed since Windows 10, v1607), I do not care that NTFS actually has no problem and supports 32,767 Unicode characters and the actual problem is the Windows API (and since v1607, apps that have not been updated to support the new behaviour). It is an example of a bug/limitation/lack-of-polish of Windows. The internal details are irrelevant.
Gnome has a lot more of these issues(thumbnails being one of the most visible and annoying ones) than Windows. Gnome (any ver) is not more polished than Windows.
I agree that the reason does not matter and is irrelevant to the end-user. I was just speculating as to why they have not "just fixed it". However, I disagree that Windows is more polished. Windows is made up of a mixture of UI frameworks/controls/apps, some going back decades. Much of this legacy is poorly integrated and even basic things like drag-and-drop doesn't work consistently. At least Gnome is consistent and they have a vision.
Thumbnail preview is a _massive_ attack surface. All those RCEs in JPEGs, MP4s, PDFs etc are now potentially immediately executed upon displaying the file. No thanks.
So turn it off if it worries you. Keep in mind thumbnail rendering is sandboxed[0]. It's Linux, the reason I like it is that it doesn't try to prevent you from doing whatever you want.
What do you do between opening the file manager and opening the image/video itself that verifies it doesn’t have any RCE exploits that other people aren’t doing?
See, the nice thing about Linux is that you can always disable what you don't like. You're never just helplessly subject to the whims of the developers.
It will until you upgrade your Ubuntu version and you open it up to find a message that "your file manager is deprecated. use this crappy fork with fewer features instead", only to have it abandoned after a few years because the devs for the fork got butthurt.
I'm so glad I ditched Linux. Got tired of losing features because of people's egos, and being told ffmpeg was deprecated when it really wasn't became the final straw.
Is that relevant to Gnome? It's used the same file manager "Nautilus" for years. Apple and Microsoft are also quite capable of killing software projects.
How long have you been using Gnome for? I'd been a while for me, but back when I was using Linux it seemed like Nautilus was frequently dropping features for things I didn't care about.
Gnome may be different now, but they were part of a pattern in the GNU/Linux community that ultimately caused me to leave it. I knew I couldn't rely on either Gnome or distros themselves because they seemed to have no problem changing things out from underneath you, and more often than not it seemed like those things were done as a form of self promotion.
This wasn't a one off thing. This was the Linux world for a good number of years, in my experience. Anyone who used Ubuntu or Debian from 2008 to around 2013 might remember the forks that happened because DEs up and decided that they knew better than their own users.
Not specifically about Gnome, but I brought up FFmpeg (or rather libav) as another example of the bullshit of Linux. Some devs decided that they didn't like the architecture of FFmpeg and wanted it to be organized to their liking, so they forked it into Libav/avconv, which was inferior to FFmpeg but the people who run the Debian repositories were convinced that Libav was the future so they replaced FFmpeg with an alias to avconv that had a totally misleading deprecation message that was basically a lie.
So yeah, it wouldn't surprise me at all if Gnome one day decided to get rid of thumbnails and not provide an option to turn them back on. Yes, I am bitter from the latter years of my Linux usage. Somehow macOS can update and upgrade its versions without causing me to question whether aspects of the UI I rely upon will spontaneously disappear or gaslight me into thinking I shouldn't be using those things anymore.
I've been using i3 up until recently. I'm trying out Gnome because it works out-of-the-box and e.g. Sway does not. Yes the software churn is rather worrying. I hope they learn from the mistakes.
The thing that irks me more than churn is not providing pathways forward. It's like, if you're going to get rid of bookmarks, then either give me an add-on that brings them back or give me time to adjust to not having bookmarks. Gnome used to be one of the worst at communicating their intentions. You never knew what you were going to get if you were going to upgrade Gnome. But I come from the philosophy of frontend JavaScript development where everything is announced, has a deprecation warnings, features extracted into libraries, and so forth. The people who work on GNU/Linux related development come off as very arrogant in their decision making, even if they aren't intending to be arrogant.
Just so people are aware, I understand that things could have changed in the last 9 years. However, those kind of user experiences can permanently ruin the reputation of OSS projects.
They kept Nautilus but have absolutely gutted it over time removing things like split panes. I think it actually had more features in GNOME 3.00 than today. I was one of the weirdos that loved GNOME 3.00 at release but I felt they've taken more steps back than forward chasing who knows what.
Multiple displays definitely work, but I had to check regarding your question about screen arrangement. That works.
Gnome version 3.38.3
Ubuntu 20.10
Thinkpad X1 Carbon 6th gen rigged to a Dell thunderbolt dock
Monitor 1 from dock via hdmi
Monitor 2 from dock via displayport