Hello,
I am not new to linux, I know that if you want the source code
in a Debian based distro as root you would type ...
apt-get source -d bash

and apt will download the source code for you.

In a Fedora based distro as root you would type in ...
dnf downlowd --source bash
and dnf will get the source code for you.

But If you have a Flatpak app for instance one called
"Ultimate Media Downloader"
How would you go about downloading the source code for it?
I would really like to know .

Thank You

Since I am going for source, and NOT as it is packaged for my distro, I bypass that whole repo thing.
Compiling from source is going to bypass your system software tools anyway, so go direct to the project or developers site and grab the source code from there. They may also have tips for building and installing a native image.

I do not recommend this for people who do not develop/code/compile their own stuff, but for those of us who do it will serve.

This will also serve if you have NO intent to compile, but need to examine the code to verify behavior. In this case just make sure you capture source for the same VERSION, because both code and behavior can change between versions.

And you should note that not all Flatpaks will have source available. Many closed packages are distributed via Snap, Flatpak, and likely a few AppImages. Just because it's released for Linux doesn't guarantee it is open source. If that matters to you that is.

Read the "Note" section at the bottom of this site
There is a "Donate" link and an email address. Use these two links properly and you might get the source code for Ultimate Media Downloader.

https://github.com/keshavbhatt/ultim...wnloader-linux

https://github.com/keshavbhatt/ultim...heads/main.zip

https://github.com/keshavbhatt/Ktube..._1.0_amd64.deb

thank you teckk .