Looks to be similar problem to: https://github.com/Revolutionary-Games/Thrive/is…sues/1505
Sadly it seems that here the problem happens so deep in the JSON serialization that I'm pretty sure we can't fix it ourselves.
From my earlier research this seems to be a mono bug.
Callstack:
```
Error Saving - Saving failed! An exception happened exception: System.ExecutionEngineException: String conversion error: Illegal byte sequence encounted in the input.
at (wrapper managed-to-native) System.Reflection.RuntimeAssembly.get_code_base(System.Reflection.Assembly,bool)
at System.Reflection.RuntimeAssembly.GetCodeBase (System.Reflection.Assembly a, System.Boolean escaped) [0x00000] in <34e7ab706f1141f9b981d74fbe2f5560>:0
at System.Reflection.RuntimeAssembly.get_CodeBase () [0x00000] in <34e7ab706f1141f9b981d74fbe2f5560>:0
at System.Reflection.AssemblyName.Create (System.Reflection.Assembly assembly, System.Boolean fillCodebase) [0x00010] in <34e7ab706f1141f9b981d74fbe2f5560>:0
at System.Reflection.RuntimeAssembly.GetName (System.Boolean copiedName) [0x0000e] in <34e7ab706f1141f9b981d74fbe2f5560>:0
at System.Reflection.Assembly.GetName () [0x00000] in <34e7ab706f1141f9b981d74fbe2f5560>:0
at BaseThriveConverter.WriteJson (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.JsonSerializer serializer) [0x00160] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeConvertable (Newtonsoft.Json.JsonWriter writer, Newtonsoft.Json.JsonConverter converter, System.Object value, Newtonsoft.Json.Serialization.JsonContract contract, Newtonsoft.Json.Serialization.JsonContainerContract collectionContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x0008a] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.Serialization.JsonContract valueContract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x00071] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type objectType) [0x00079] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerProxy.SerializeInternal (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type rootType) [0x00008] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonSerializer.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value) [0x00000] in <2676a2da6edc420e890ed28aa4572ee5>:0
at BaseThriveConverter.WriteMember (System.String name, System.Object memberValue, System.Type memberType, System.Type objectType, Newtonsoft.Json.JsonWriter writer, Newtonsoft.Json.JsonSerializer serializer) [0x00012] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at BaseThriveConverter.WriteJson (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.JsonSerializer serializer) [0x00226] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeConvertable (Newtonsoft.Json.JsonWriter writer, Newtonsoft.Json.JsonConverter converter, System.Object value, Newtonsoft.Json.Serialization.JsonContract contract, Newtonsoft.Json.Serialization.JsonContainerContract collectionContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x0008a] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.Serialization.JsonContract valueContract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x00071] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type objectType) [0x00079] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerProxy.SerializeInternal (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type rootType) [0x00008] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonSerializer.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value) [0x00000] in <2676a2da6edc420e890ed28aa4572ee5>:0
at BaseThriveConverter.WriteMember (System.String name, System.Object memberValue, System.Type memberType, System.Type objectType, Newtonsoft.Json.JsonWriter writer, Newtonsoft.Json.JsonSerializer serializer) [0x00012] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at BaseThriveConverter.WriteJson (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.JsonSerializer serializer) [0x00226] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeConvertable (Newtonsoft.Json.JsonWriter writer, Newtonsoft.Json.JsonConverter converter, System.Object value, Newtonsoft.Json.Serialization.JsonContract contract, Newtonsoft.Json.Serialization.JsonContainerContract collectionContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x0008a] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.Serialization.JsonContract valueContract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x00071] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.Serialization.JsonObjectContract contract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract collectionContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x0008d] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter writer, System.Object value, Newtonsoft.Json.Serialization.JsonContract valueContract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerProperty) [0x000b2] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type objectType) [0x00079] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonSerializer.SerializeInternal (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type objectType) [0x0023a] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonSerializer.Serialize (Newtonsoft.Json.JsonWriter jsonWriter, System.Object value, System.Type objectType) [0x00000] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonConvert.SerializeObjectInternal (System.Object value, System.Type type, Newtonsoft.Json.JsonSerializer jsonSerializer) [0x00028] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonConvert.SerializeObject (System.Object value, System.Type type, Newtonsoft.Json.Formatting formatting, Newtonsoft.Json.JsonSerializerSettings settings) [0x0000e] in <2676a2da6edc420e890ed28aa4572ee5>:0
at Newtonsoft.Json.JsonConvert.SerializeObject (System.Object value, Newtonsoft.Json.Formatting formatting, Newtonsoft.Json.JsonSerializerSettings settings) [0x00000] in <2676a2da6edc420e890ed28aa4572ee5>:0
at ThriveJsonConverter+<>c__DisplayClass9_0.<SerializeObject>b__0 (Newtonsoft.Json.JsonSerializerSettings settings) [0x00000] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at ThriveJsonConverter.PerformWithSettings[T] (System.Func`2[T,TResult] func) [0x00033] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at ThriveJsonConverter.SerializeObject (System.Object o) [0x0000d] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at Save.SaveToFile () [0x0002c] in <edbb8fde198a4f7f885b551d24b27a7a>:0
at SaveHelper.PerformSave (InProgressSave inProgress, Save save) [0x00000] in <edbb8fde198a4f7f885b551d24b27a7a>:0
```