https://git.suckless.org/surf/commit/7f1156f9b0977a72e523e031cf67a4946cfee9b2.html

Index: config.mk
--- config.mk.orig
+++ config.mk
@@ -4,18 +4,18 @@ VERSION = 2.1
 # Customize below to fit your system
 
 # paths
-PREFIX = /usr/local
-MANPREFIX = $(PREFIX)/share/man
+PREFIX ?= /usr/local
+MANPREFIX ?= $(PREFIX)/man
 LIBPREFIX = $(PREFIX)/lib
 LIBDIR = $(LIBPREFIX)/surf
 
 X11INC = `pkg-config --cflags x11`
 X11LIB = `pkg-config --libs x11`
 
-GTKINC = `pkg-config --cflags gtk+-3.0 gcr-3 webkit2gtk-4.0`
-GTKLIB = `pkg-config --libs gtk+-3.0 gcr-3 webkit2gtk-4.0`
-WEBEXTINC = `pkg-config --cflags webkit2gtk-4.0 webkit2gtk-web-extension-4.0 gio-2.0`
-WEBEXTLIBS = `pkg-config --libs webkit2gtk-4.0 webkit2gtk-web-extension-4.0 gio-2.0`
+GTKINC = `pkg-config --cflags gtk+-3.0 gcr-3 webkit2gtk-4.1`
+GTKLIB = `pkg-config --libs gtk+-3.0 gcr-3 webkit2gtk-4.1`
+WEBEXTINC = `pkg-config --cflags webkit2gtk-4.1 webkit2gtk-web-extension-4.1 gio-2.0`
+WEBEXTLIBS = `pkg-config --libs webkit2gtk-4.1 webkit2gtk-web-extension-4.1 gio-2.0`
 
 # includes and libs
 INCS = $(X11INC) $(GTKINC)
