@WhyJiffie@sh.itjust.works please update your link

Again, no.

Not sure what platform you're on but on Linux flatpak can limit access to files, and things like AppArmor can do that for any native app as well (though it can be pretty tedious to configure)

how are programs denied that access? how is it that they can't do that?

with the computers that I know, if I download a program, that'll be able to read, and also modify all the files that I have access to. this includes the ability to read the saved passwords from my browser, and to install browser addons without my consent or knowledge.

what makes it so that it cannot happen on mainstream desktop computers?

on linux. flatpak. now, how mainstream is that setup exactly? are you saying that the issue I brought up does not apply to most of the people on the internet?

it does not matter what platform I'm on. what matters is what do most people use. in the world where I live, most people use the windows operating system. there is no such protection at all. except when accounting for sandboxie and other obscure programs virtually no one knows about

how are programs denied that access? how is it that they can't do that?

Apps are typically given their own dedicated storage volume, and access to any other part of the filesystem requires permission from the user.

this includes the ability to read the saved passwords from my browser, and to install browser addons without my consent or knowledge.

WTF kind of computers are you using?

Apps are typically given their own dedicated storage volume, and access to any other part of the filesystem requires permission from the user.

uh, no? on smartphones, yes, but not on computers.

and even on smartphones. the chat app does have access to your messages, as I originally said

WTF kind of computers are you using?

desktop.. computers? you probably heard about operating systems, like windows, and linux..

uh, no?

Uh, yes.

the chat app does have access to your messages, as I originally said

What you originally said was gibberish, but I digress. The chat app is open source, so you can evaluate what it's doing with those messages for yourself.

uh, no? on smartphones, yes, but not on computers.

That's not true. Most operating systems at least have filesystem permissions, and on a lot of Linux distros you additionally get AppArmor or PolKit to further restrict what files a program can read/write.

I mentioned Linux specifically because something like this is the hardest to set up on Linux. I (wrongly) assumed that since you were complaining about it not existing, you were on a platform where setting these permissions up isn't straightforward. App-specific file-acess permissions are on MacOS out of the box as a configurable setting for all applications (in the system settings menu), and I'm pretty sure Windows 10/11 has something similar in its settings menu as well.

Edit:
Also, if we're being pedantic, this is also a setting on both Android and iOS, with Android displaying the option to change access pretty much every time you pick out a file.

But its not a simple messenger though. If you want something simple, IRC is always available for use.