diff --git a/src/main/java/me/clip/placeholderapi/expansion/manager/LocalExpansionManager.java b/src/main/java/me/clip/placeholderapi/expansion/manager/LocalExpansionManager.java
index 214179e..ae56188 100644
--- a/src/main/java/me/clip/placeholderapi/expansion/manager/LocalExpansionManager.java
+++ b/src/main/java/me/clip/placeholderapi/expansion/manager/LocalExpansionManager.java
@@ -411,6 +411,14 @@ public final class LocalExpansionManager implements Listener {
   private void unregisterAll() {
     for (final PlaceholderExpansion expansion : Sets.newHashSet(expansions.values())) {
       if (expansion.persist() || expansion.getExpansionType() == Type.INTERNAL) {
+        // Print warning if an external expansion is set to be persistent.
+        if (expansion.getExpansionType() == Type.EXTERNAL && expansion.persist()) {
+          Msg.warn("Nag author(s) %s about their expansion %s being marked as \"external\" "
+              + "but having persist() set to true!", expansion.getAuthor(), expansion.getIdentifier());
+          Msg.warn("External Expansions should not be set to be persistent! PlaceholderAPI "
+              + "will respect this setting and skip the unregister of this Expansion...");
+        }
+        
         continue;
       }