diff --git a/core/src/com/unciv/logic/GameSaver.kt b/core/src/com/unciv/logic/GameSaver.kt
index cd684e82e5..0b815f3b39 100644
--- a/core/src/com/unciv/logic/GameSaver.kt
+++ b/core/src/com/unciv/logic/GameSaver.kt
@@ -69,11 +69,11 @@ class GameSaver {
     }
 
     fun autoSave(gameInfo: GameInfo, postRunnable: () -> Unit = {}) {
+        // The save takes a long time (up to a few seconds on large games!) and we can do it while the player continues his game.
+        // On the other hand if we alter the game data while it's being serialized we could get a concurrent modification exception.
+        // So what we do is we clone all the game data and serialize the clone.
         val gameInfoClone = gameInfo.clone()
         kotlin.concurrent.thread {
-            // the save takes a long time (up to a second!) and we can do it while the player continues his game.
-            // On the other hand if we alter the game data while it's being serialized we could get a concurrent modification exception.
-            // So what we do is we clone all the game data and serialize the clone.
             saveGame(gameInfoClone, "Autosave")
 
             // keep auto-saves for the last 10 turns for debugging purposes
diff --git a/core/src/com/unciv/models/gamebasics/Building.kt b/core/src/com/unciv/models/gamebasics/Building.kt
index 5ce628be0d..258f2d406e 100644
--- a/core/src/com/unciv/models/gamebasics/Building.kt
+++ b/core/src/com/unciv/models/gamebasics/Building.kt
@@ -163,8 +163,7 @@ class Building : NamedStats(), IConstruction{
     }
 
     fun getStatPercentageBonuses(civInfo: CivilizationInfo?): Stats {
-        val stats = percentStatBonus
-        if(stats==null) return Stats() // empty
+        val stats = if(percentStatBonus==null) Stats() else percentStatBonus!!.clone()
         if(civInfo==null) return stats // initial stats
 
         val adoptedPolicies = civInfo.policies.adoptedPolicies