Little git confusion

I pushed nice little local repo with 4 branches to this remote. Before that remote was empty, just created.

When i entered command:

git push --all <REMOTE-NAME>

The HEAD pointer was on master, master was also first created branch.

But for some reason, as you can see at the link above, layuot shifter became default branch on GitHub website.

Why? No clue. Did I mess up? Is it an issue at all?

Some Git bash right now looks like:
note: username in a native language, dont be confused

Матрос Дмитриев (master) flexBoxDesignPatterns
$ git branch -a
  layoutShifter
* master
  mostlyFluid
  offCanvas
  remotes/origin/layoutShifter
  remotes/origin/master
  remotes/origin/mostlyFluid
  remotes/origin/offCanvas
Матрос Дмитриев (master) flexBoxDesignPatterns
$ git log --oneline --graph -a
* defa68d (HEAD -> master, origin/offCanvas, origin/mostlyFluid, origin/master, origin/layoutShifter, offCanvas, mostlyFluid, layoutShifter) height adjusted
* 3910a1f set breakpoints
* 9be7c37 update TODOs
* e3c9551 basic smallscreen layout
* b87f980 Initial commit
Матрос Дмитриев (master) flexBoxDesignPatterns
$ git --version
git version 2.36.1.windows.1

Looking at the repo in Github, it looks like layoutShifter is the same as master.
If you want to switch the default branch, you can follow these steps:Changing the default branch - GitHub Docs

You mean all files and code inside are identical? Yes, that is correct. I’ve just created 3 new branches(master was from the beginning) but not worked on them yet.

Maybe that’s why GiHub kinda randomly chose default branch?

It is not random. Whatever the first branch you push up to GitHub is becomes the default branch on GitHub.

So I needed somehow specify, which of 4 branches should become default?
I was pushing all 4 branches at once(with flag --all) into empty remote.

Typically, a branch named main is default but it really can be anything you want it to be. You can change the default branch on GitHub.

Most of the time, you only push one branch at a time (the one your are currently working on).