#vimtrick
q: repeat last colon command
a: first `@:`, further repeats `@@`

https://vim.fandom.com/wiki/Repeat_last_colon_command

Repeat last colon command

The last command entered with':' can be repeated with@: and further repeats can be done with@@ This is useful for commands like:bnext or:cNext.

@jartigag So ":" is an macro buffer that is automatically updated with the last colon command? Interesting!

Not that I use Vim anymore, but...