SUMMARY
The starting point of comment syntax should be right after the indentation of the commented line. Currently Kate's comment shortcut (Ctrl+/) puts the comment syntax at the very beginning of the line, without regard to the indentation.

This bug will cause auto-formatting tools like clang-format to indent the commented line once again.

STEPS TO REPRODUCE
1. Example code:
main.cc
----
#include <iostream>
int
main()
{
  std::cout << "Hello World!" << std::endl;
  {
    std::cout << "Hello World!" << std::endl;
    {
      std::cout << "Hello World!" << std::endl;
    }
  }
}
----

2. Press Ctrl+/ to comment the hello-worlds.


OBSERVED RESULT

Indentations by Ctrl+/
<main.cc>
----
#include <iostream>
int
main()
{
//   std::cout << "Hello World!" << std::endl;
  {
//     std::cout << "Hello World!" << std::endl;
    {
//       std::cout << "Hello World!" << std::endl;
    }
  }
}
----

Result from "clang-format --style=Mozilla main.cc":
<main.cc>
----
#include <iostream>
int
main()
{
  //   std::cout << "Hello World!" << std::endl;
  {
    //     std::cout << "Hello World!" << std::endl;
    {
      //       std::cout << "Hello World!" << std::endl;
    }
  }
}
----


EXPECTED RESULT

Comments in respect of indentations:
<main.cc>
----
#include <iostream>
int
main()
{
  // std::cout << "Hello World!" << std::endl;
  {
    // std::cout << "Hello World!" << std::endl;
    {
      // std::cout << "Hello World!" << std::endl;
    }
  }
}
----

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora
KDE Plasma Version: 5.17.5
KDE Frameworks Version: 5.67.0 
Qt Version: 5.13.2

ADDITIONAL INFORMATION
None