This should do the trick:
diff --git a/gnu/packages/gnuzilla.scm b/gnu/packages/gnuzilla.scm
index d5d9839e1a..e9458037a5 100644
--- a/gnu/packages/gnuzilla.scm
+++ b/gnu/packages/gnuzilla.scm
@@ -1023,7 +1023,11 @@ from forcing GEXP-PROMISE."
(format #t "configure flags: ~s~%" flags)
(apply invoke bash
(string-append srcdir "/configure")
- flags))))
+ flags)
+ ;; Remove references to store items
+ (substitute* "toolkit/content/buildconfig.html"
+ (("/gnu/store") ""))
+ #t)))
(replace 'build
;; The build system often spuriously fails. See
;; <https://bugs.gentoo.org/show_bug.cgi?id=680934>. To
--
Ricardo
