diff --git a/Makefile b/Makefile
index 133c891..090fca3 100644
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,7 @@ USERCHROME_FILES := $(sort $(wildcard src/userChrome/*.css))
 HOMEPAGE_FILES := head.html distro_links.html bottom.html
 DISTRO := postmarketOS
 DESTDIR :=
+FIREFOX_DIR := /usr/lib/firefox
 
 all: out/home.html out/userChrome.css
 
@@ -25,7 +26,7 @@ install: all
 	install -Dm644 src/policies.json \
 		"$(DESTDIR)/etc/firefox/policies/policies.json"
 	install -Dm644 src/prefs.js \
-		"$(DESTDIR)/usr/lib/firefox/defaults/pref/mobile-config.js"
+		"$(DESTDIR)/$(FIREFOX_DIR)/defaults/pref/mobile-config.js"
 	install -Dm644 "out/home.html" \
 		"$(DESTDIR)/usr/share/mobile-config-firefox/home.html"
 	install -Dm644 "out/userChrome.css" \