diff --git a/core/src/com/unciv/logic/civilization/diplomacy/DiplomacyManager.kt b/core/src/com/unciv/logic/civilization/diplomacy/DiplomacyManager.kt
index 3db2f00db9..93785dc057 100644
--- a/core/src/com/unciv/logic/civilization/diplomacy/DiplomacyManager.kt
+++ b/core/src/com/unciv/logic/civilization/diplomacy/DiplomacyManager.kt
@@ -102,8 +102,12 @@ enum class DiplomaticModifiers(val text: String) {
     GaveUsUnits("You gave us units!"),
     GaveUsGifts("We appreciate your gifts"),
     ReturnedCapturedUnits("You returned captured units to us"),
-    BelieveSameReligion("We believe in the same religion"),
+    BelieveSameReligion("We believe in the same religion");
 
+    companion object{
+        private val valuesAsMap = DiplomaticModifiers.values().associateBy { it.name }
+        fun safeValueOf(name: String) = valuesAsMap[name]
+    }
 }
 
 class DiplomacyManager() : IsPartOfGameInfoSerialization {
@@ -113,7 +117,6 @@ class DiplomacyManager() : IsPartOfGameInfoSerialization {
         const val MINIMUM_INFLUENCE = -60f
     }
 
-    @Suppress("JoinDeclarationAndAssignment")  // incorrect warning - constructor would need to be higher in scope
     @Transient
     lateinit var civInfo: Civilization
 
diff --git a/core/src/com/unciv/ui/screens/diplomacyscreen/MajorCivDiplomacyTable.kt b/core/src/com/unciv/ui/screens/diplomacyscreen/MajorCivDiplomacyTable.kt
index ba9793bb9a..a38982814b 100644
--- a/core/src/com/unciv/ui/screens/diplomacyscreen/MajorCivDiplomacyTable.kt
+++ b/core/src/com/unciv/ui/screens/diplomacyscreen/MajorCivDiplomacyTable.kt
@@ -199,7 +199,9 @@ class MajorCivDiplomacyTable(private val diplomacyScreen: DiplomacyScreen) {
                 && otherCivDiplomacyManager.hasModifier(DiplomaticModifiers.DestroyedProtectedMinor))
                 continue
 
-            var text = DiplomaticModifiers.valueOf(modifier.key).text.tr() + " "
+            val diplomaticModifier = DiplomaticModifiers.safeValueOf(modifier.key)
+                ?: continue // This modifier is from the future, you cannot understand it yet
+            var text = diplomaticModifier.text.tr() + " "
             if (modifier.value > 0) text += "+"
             text += modifier.value.roundToInt()
             val color = if (modifier.value < 0) Color.RED else Color.GREEN