Rebinding 'yy' (yank line) is not working

[bodgergely]

Describe the bug
Unable to rebind the yank line command "yy" to "ff" (or any other key)
Since I have succefully remapped 'y' to 'f' I also expect the 'ff' to yank a line in normal mode.
To Reproduce
Steps to reproduce the behavior:

    "vim.visualModeKeyBindings": [
        {
            "before": [
                "f"
            ],
            "after": [
                "y"
            ]
        }
    ],
    "vim.normalModeKeyBindings": [
        {
            "before": [
                "f"
            ],
            "after": [
                "y"
            ]
        }
    ],

Now if you try using 'ff' to yank a line it will not work.

Expected behavior

'ff', just like 'yy' should yank a line.

Environment (please complete the following information):
VSCode version: 1.12.2
Linux

• Extension (VsCodeVim) version:
• VSCode version: 1.12.2
• OS: Linux

[J-Fields]

nnoremap ff yy does what you want

[bodgergely]

@J-Fields Thanks a lot, worked!

[mdshahjalal5]

nnoremap ff yy does what you want

I not understood what to do here