diff --git a/doc/notes/3.1.3.md b/doc/notes/3.1.3.md
index 8d27c3e7eb..8c35f088aa 100644
--- a/doc/notes/3.1.3.md
+++ b/doc/notes/3.1.3.md
@@ -50,6 +50,10 @@ This build includes the following changes:
     * Callback and struct classes.
     * Struct members.
     * Function parameters and return values.
+- The default memory allocator on Windows is now the system allocator instead of jemalloc.
+    * jemalloc is not properly optimized for Windows and its performance is not competitive.
+    * jemalloc is still a major performance win on Linux and macOS.
+    * rpmalloc is faster on all platforms but requires per-thread setup, so must be enabled manually.  
 
 #### Fixes
 
diff --git a/modules/core/src/main/java/org/lwjgl/system/MemoryManage.java b/modules/core/src/main/java/org/lwjgl/system/MemoryManage.java
index 863507ead2..173ae7600c 100644
--- a/modules/core/src/main/java/org/lwjgl/system/MemoryManage.java
+++ b/modules/core/src/main/java/org/lwjgl/system/MemoryManage.java
@@ -26,7 +26,7 @@ static MemoryAllocator getInstance() {
             return (MemoryAllocator)allocator;
         }
 
-        if (!"system".equals(allocator)) {
+        if (!((allocator == null && Platform.get() == Platform.WINDOWS) || "system".equals(allocator))) {
             String className;
             if (allocator == null || "jemalloc".equals(allocator)) {
                 className = "org.lwjgl.system.jemalloc.JEmallocAllocator";