diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6fc5d39..b297fa2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2101.1.6]
+
+### Fixed
+* Fixed cross-mod compat issue causing crashes under some situations when players join
+
 ## [2101.1.5]
 
 ### Changed
diff --git a/common/src/main/java/dev/ftb/mods/ftblibrary/FTBLibrary.java b/common/src/main/java/dev/ftb/mods/ftblibrary/FTBLibrary.java
index ee9ceb8..7590c4f 100644
--- a/common/src/main/java/dev/ftb/mods/ftblibrary/FTBLibrary.java
+++ b/common/src/main/java/dev/ftb/mods/ftblibrary/FTBLibrary.java
@@ -52,6 +52,9 @@ private void serverStopped(MinecraftServer server) {
     }
 
     private void playerJoined(ServerPlayer player) {
-        NetworkHelper.sendTo(player, new SyncKnownServerRegistriesPacket(KnownServerRegistries.server));
+        if (KnownServerRegistries.server != null) {
+            // can be null, e.g. https://github.com/FTBTeam/FTB-Mods-Issues/issues/1387
+            NetworkHelper.sendTo(player, new SyncKnownServerRegistriesPacket(KnownServerRegistries.server));
+        }
     }
 }
diff --git a/gradle.properties b/gradle.properties
index 133fb1b..c7459d8 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -3,7 +3,7 @@ org.gradle.daemon=false
 # Mod
 mod_id=ftblibrary
 readable_name=FTB Library
-mod_version=2101.1.5
+mod_version=2101.1.6
 mod_author=FTB Team
 # Maven
 archives_base_name=ftb-library