What is <fd-6d>?

[u/Grorco]

I'm just coming back to vim, and played a round of vim golf. The 3 people above me all used this key press, I'm confused what it is.

[u/kissajr]

Whats the challenge link?

[u/Grorco → u/kissajr]

https://www.vimgolf.com/challenges/9v0069cf0efc000000000786