I want that as well, but I don't think it's practical to do that on the Linux desktop ecosystem. Too slow, too much politics. The gist of it is done by Android though, but that required extensive re-engineering of the user space.

Risking getting down voted but I don't want to repeat myself: https://news.ycombinator.com/item?id=43255985

I would love the capabilities you describe, but I don't think it's fair to call flatpak "mostly theater." Yes plenty of flatpak apps require you to broaden their perms to the point where the sandbox starts to feel pretty weak, and there is plenty more to do on the system, but I think it's a good step forward.

Then it's never going to happen.

Linux desktop is a huge mountain of "why this basic obvious stuff just doesn't work?"

I mean just stop to consider this. It's 2025. You are still not guaranteed to be able to close an application by moving the mouse all the way to the top right and clicking, because sometimes the X button has a margin at the top. This is insane to me. This is like such a basic thing that I have no idea how do you even manage to get it wrong.

If Linux can't even get the X button right, do you seriously expect anything else to ever get fixed?

I believe this is part of what [Spectrum OS](https://spectrum-os.org/) is ultimately trying to do. That said, while it’s being actively developed, it’s not a trivial effort and is nowhere near “download the iso and daily drive it”.

That reminds me of something iOS is doing (though I don't know when it was introduced).

An app wanted permission to my photos. In addition to the normal "Allow" and "Deny" options, I was also given the option to allow a subset of photos. I chose that option, and was given the normal photos UI, as if I was selecting a set of photos to share or delete. I guess in the back-end, iOS constructed a new photos library consisting of just the ones I selected.

It was cool! And it's good to see things at least one of the things you describe is being shown to a large number of folks. Hopefully that'll drive momentum to wider adoption.

> When it asks me to open a file, or a directory, it should invoke a system dialog that cannot be faked, and when I pick a file/directory for it, that directory or file should be bind-mounted into its mount namespace without giving it extra information about other files beside it, or indeed what's the full path of the file. When recording a screen, I should be able to pick which regions and which applications it should be able to see, and the system should make it think it's all there is.

You've described exactly what flatpak is doing? I'm curious what gaps you see with its approach in particular.

> I'd like to have a system where I can choose to give any bitmap, movie, or blank screen when an application asks me for permission to use my camera. When it asks for my microphone, I should be able to choose to make it think I allowed it microphone access with dummy audio stream with no audio or audio of my choice.

It is what I had thought too (you could also provide a filter, or the video and/or audio output of another program, or other stuff), and I have also seen others with similar ideas than that as well. (It also does not know whether or not you even have a camera or microphone; this way, you can use a program that expects a camera even if you do not have it.)

Although it could be made with Linux and existing systems, my idea was to redesign the entire operating system and computer to support this in order to work better. There is some issues which are not handled by the existing systems, including some fingerprinting, and date/time, and some others.

> When it asks me to open a file, or a directory, it should invoke a system dialog that cannot be faked, and when I pick a file/directory for it, that directory or file should be bind-mounted into its mount namespace without giving it extra information about other files beside it, or indeed what's the full path of the file.

This would be insufficient for many uses, e.g. if a file name is specified by command-line arguments or by configuration files, or if the program does care about other files with a similar name (which SQLite does, so many programs that use SQLite also will). (I had thought of how a sandbox library could be made to support some of these things could be made on Linux, although I had never actually designed or implemented it.)

> When recording a screen, I should be able to pick which regions and which applications it should be able to see, and the system should make it think it's all there is.

Yes, I agree, it is also a good idea. But, screen recording will also be video input, which the camera also is, so it might work in a similar way.

> I think the pieces to do this are mostly there already (portals, Pipewire, namespaces)

I also think there is problems with the ways some of these things are working. One is that the system will use ambient authority (which is one reason why I had suggested to make up a new operating system instead), and some of the protocols expect use of Unicode and do not support other character sets so well, and the existing sandboxing also does not work very well for user-specified commands to use with popen (many of my own programs do use user-specified commands with popen).

> When recording a screen, I should be able to pick which regions and which applications it should be able to see, and the system should make it think it's all there is.

This is the norm under Flatpak + pipewire for single application captures. For full screen captures, Niri supports blanking specific windows from appearing in captures.

It is better when you cannot get a package otherwise, so if you use a distro with a big repo, it happens mostly with proprietary software.

> package everything into the image" projects

But Flatpak does not do this. It consists of runtimes that usually contain the most of what applications needed, and are updated separately from the application itself.

Have you as a user never encountered dependency hell??

Who are you and how can we trade places?

Because shipping the runtime with the software means you can get newer software on older distributions. It's also great for immutable/atomic systems where installing packages at the system level is an anti pattern.