Looking for a theme that looks like this

Paper GTK theme is a little bit similar, though with more vibrant colours ofc.
- My problem with that theme is that it doesn't highlight any buttons. I believe all buttons should have borders, especially the ones the titlebar. This helps distinguish a noninteractive label from an interactive clickable button.

https://www.pling.com/p/2142966/
Maybe not all that close, but it's the best I can think of right now.
I think it has the general old school vibe, maybe you could tweak the colors to be a bit brighter like your example?
- Love it, thanks!
- Themes like this 🤤🤤
- I'm motivated to try converting my nix-os install from gnome to plasma again
- Beautiful

I really dig this aesthetic, man. I think it's time to learn how to build a theme.

Man, my tastes are weird because as much as I LOVE dark mode, I would absolutely rock a theme like this.
A lot of the suggestions in the comments kinda miss the mark... What we want is a very flat 2D-ish theme with over exaggerated shadowing, simple icons, and gentle rounded text areas and windows. None of the elements give the appearance of 3D curves or crevices. They remind me more of stickers.
One thing that bugs me with that mockup (and sorry because you won't be able to unsee it) is the inconsistency in shadows - some buttons have it, some don't. Some icons have it, some don't.
It is otherwise a really clean and nice layout. I dig the retro warm vibes.
- The buttons with the shadow are the ones that will work with the return/enter key. It’s intentional and a convention from early Mac OS.
  This design is basically a color version of the early Mac desktop. With vector designs that are used on the current MacOS.
- it seems like a generated image possibly which is why the subtle styling is inconsistent (not that it matters).
  i don’t hate the non-shadow vs shadow effect tho… maybe just windows could be shadowed? or maybe the shadow could be like ellipses and indicate that something opens a dialog/new thing instead of a single file?
  
  Consistent font, text readable, pixel perfect consistency on close / maximize / minimize buttons. Definitely not (completely) AI-generated.
  
  Yeah, I think the same - AI generated.
  Shadow on the active window and maybe the selected icon could look nice. Likewise, on a button that is selected or hovered over.

XFCE looks closest shape-wise. it also has the advantage that you can customise it using css.
while not exactly what you're looking for, DesktopPal97 may be worth looking into as a base for your own theme.

It almost looks like an old BeOS theme maybe? This Haiku one for GTK isn't too far off, so maybe you can start with this and alter it how you like: https://github.com/B00merang-Project/Haiku

Where did you got this image from? Knowing its origin could help find the source of the theme, if it is at all an existing theme.
- Found it on some Japanese image aggregator website, I can't remember how I came across it, just that I liked it esthetically.
- That image seems to be on stock image sites like this one. So it's just an image. Didn't see any version that is converted to an actual theme.

I don't know of a specific theme in the neubrutalism/neobrutalism style (names that are generally used to describe this style or aesthetic), but it shouldn't be too hard to make.
For anyone unfamiliar it's generally defined by flat, blocky layouts, with thick borders, single color drop shadows and a few bold high contrast colors (think CGA and EGA monitors if you're that old). It often features “unpolished” elements like flat simple shapes. Bold fonts and monospace fonts are pretty common.
There are a few resources out there if anyone wants to play around with this style.
https://github.com/ComradeAERGO/Awesome-Neobrutalism https://dribbble.com/shots/20764973-Neobrutalism-UI-How-to https://www.nngroup.com/articles/neobrutalism/

I want this so bad. Although in practice I imagine none of this will fit together well with the YouTube interface or with a custom desktop background.
- what does fit well with the youtube interface though?
  
  if only they made the thumbnails just a little bit bigger. My monitor still fits 9 of them, tsk tsk
  
  Gnome maybe?

HomerOS here we come

It looks like the kind of interface they’d use in classic Pokemon or Stardew Valley. I like the colours.

Neubrutalism?
I was developing a widget toolkit that implements neubrutalsim but it's defunct now... Fuck life

I'd suppose if you ask this on KDE Reddit someone with enough time could make something like this with Kvantvm, though the difficult parts would be (1) the web browser theme, and specially (2) the icon theme - I have never ever seen an icon theme like that for Linux

Interesting idea of icons and windows sharing the same plane...

Reminds me a bit of the old default Gtk look. Or maybe early Java Swing... The flat look, primary colors, and some other elements to me; it's very nostalgic. Not sure of any themes that fit it though, sorry, haha

really nice! I guess it's a tiling window manager that arranges desktop icons too?
Yellow bars for inputs/dialogs, Blue for general popups(?), orange for errors and file managers, and white for tabbed windows/browsers.

Reminds me of the old Gem desktop for DOS.

Has anyone not mentioned Openbox yet? Window decorations look like the NeXT style, just colourful.

Looks like might be a mockup and not real theme
https://www.techradar.com/computing/software/what-is-an-operating-system
- Yes, it's a mockup, not looking for this exactly but a similar vibe/look.
- All themes start as mockups

Possibly easier achieved with a window manager than a desktop.

I used Google Lens on the picture and it brought up a lot of sites like Shutterstock. If you're better with icons than me you can probably do something with it.

It reminds me of bOS.
- Or CDE
  
  I have flashes of Solaris in my mind :)

Looks like the design of LCARS (Star trek).
So you may like this theme or similar to this one.
- Are you a bot lmao it looks nothing like lcars
  
  Well, those windows reminded me of this old VLC skin.
  And no, not a bot. Just a random internet user.
- I can see it, but this is a 17 year old Metacity theme, thanks for the effort though :-)
  
  Well that was the quickest random result I had while searching on mobile. Just to pave the way at least :)
- OP's example is like LCARS only in that they both share some colours.

Your answer is $(echo )
- I honestly don't understand what you mean by that.
  
  In bash, $(command) is replaced with output of command when run. This command has no output.
  
  My guess is that it should infinitely call echo on itself where the $() substitutes the command echo into the terminal, which calls it with echo.