Hmm...  Looks like a unified diff to me...
The text leading up to this was:
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|diff -up dmenu-4.9-b/config.def.h dmenu-4.9-a/config.def.h
|--- dmenu-4.9-b/config.def.h	2019-02-02 13:55:02.000000000 +0100
|+++ dmenu-4.9-a/config.def.h	2019-05-19 02:10:12.740040403 +0200
--------------------------
Patching file config.def.h using Plan A...
Hunk #1 succeeded at 21.
Hmm...  The next patch looks like a unified diff to me...
The text leading up to this was:
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|diff -up dmenu-4.9-b/dmenu.c dmenu-4.9-a/dmenu.c
|--- dmenu-4.9-b/dmenu.c	2019-02-02 13:55:02.000000000 +0100
|+++ dmenu-4.9-a/dmenu.c	2019-05-19 02:11:20.966710117 +0200
--------------------------
Patching file dmenu.c using Plan A...
Hunk #1 succeeded at 654.
done