Hi Stefan,

your patch file arrived mangled in my mailbox.

On Sun, 13 Dec 2020 18:25:24 +0100
Stefan <stefan-guix@vodafonemail.de> wrote:

>diff --git a/gnu/bootloader/grub.scm b/gnu/bootloader/grub.scm
>index af7b7561ff..3177452dfb 100644
>--- a/gnu/bootloader/grub.scm
>+++ b/gnu/bootloader/grub.scm
>@@ -191,9 +191,18 @@ fi~%"
>  (define font-file

For example, the original source file had here two spaces before the "define".
But the Patch format needs one control character in front.

In this case (for the Context mark), the control character should also be a
space.
That means there should be three spaces there.  But there are two spaces there.

It goes on similarly in the entire patch file.

I've fixed it up manually and pushed to guix master--but you might want
to look into why this happens in general before something important gets
mangled.