[bjg]

I run pentadactyl, and vimperator before pentadactyl was around.

What does that have to do with the keyboard shortcuts on github's home page?

[th]

I don't run pentadactyl but it looks like it supports vim-style macros. I assume it would be something like qAjx to create the macro and 25@A to use it if j and x pass through to the page properly.