diff -up thunderbird-52.0/mozilla/memory/mozjemalloc/jemalloc.c.852698 thunderbird-52.0/mozilla/memory/mozjemalloc/jemalloc.c
--- thunderbird-52.0/mozilla/memory/mozjemalloc/jemalloc.c.852698	2017-04-04 10:32:15.667281885 +0200
+++ thunderbird-52.0/mozilla/memory/mozjemalloc/jemalloc.c	2017-04-04 10:35:15.907018486 +0200
@@ -1096,7 +1096,7 @@ static const bool config_recycle = false
  * controlling the malloc behavior are defined as compile-time constants
  * for best performance and cannot be altered at runtime.
  */
-#if !defined(__ia64__) && !defined(__sparc__) && !defined(__mips__) && !defined(__aarch64__)
+#if !defined(__ia64__) && !defined(__sparc__) && !defined(__mips__) && !defined(__aarch64__) && !defined(__powerpc__)
 #define MALLOC_STATIC_SIZES 1
 #endif