Known Issues

This section lists the known bugs and issues with the AltTester® Unity SDK. If available, we list a workaround to help troubleshoot the issue.

To report a bug that isn’t listed here, see our Contributing section to learn how to best report the issue.


Calling GetPNGScreenshot throws StackOverflow error (.NET Driver)

Problem: For high resolutions calling GetPNGScreenshot might throw a StackOverflow error.

Workaround: The issue only happens with .NET 6. As a workaround you can use .NET 5, or if you can’t downgrade to .NET 5, try to run your tests with a lower resolution until this issue is fixed.

Affects: AltUnity Tester v1.7.* and AltTester® Unity SDK v1.8.* with .NET 6

New Input System

Touch or Mouse actions do not work in tests

Workaround: In Analysis -> Input Debugger -> Options make sure the setting Simulate Touch Input From Mouse or Pen is not checked and Lock Input to Game View is checked.

Affects: AltUnity Tester v1.7.1, v1.7.2, AltTester® Unity SDK v1.8.*, v2.0.0 and Input System with a version below 1.3.0

The PressKey command does not work

Workaround: This issue might happen if your code uses the methods wasPressedThisFrame and wasReleasedThisFrame*. Use isPressed instead.

Affects: AltUnity Tester v1.7.1, v1.7.2, AltTester® Unity SDK v1.8.*, v2.0.x, v2.x

Player Input is not working when connected to AltTester® Unity SDK/Desktop

Problem: Player Input is not working in the instrumented build when connected to the tests or to AltTester® Desktop.

Affects: All input actions created with the New Input System for app objects. The New Input System actions for UI objects are not affected, as well as the Old Input System actions.

AltTester® Editor

Playing in Editor throws EntryPointNotFoundException: WebSocketSetOnOpen assembly:<unknown assembly> type:<unknown type> member:(null)

Problem: The WebGL platform was previously selected (check Project Settings) and when playing in Editor the WebSocket is trying to compile the WebGL script

Workaround: Select a platform other than WebGL before Editor and if the error is still thrown while playing in Editor re-start de Unity project

Affects: AltTester® Unity SDK v2.0.x, v2.x

Play in Editor does not start the instrumented app in the Unity Editor

Problem: If Keep ALTTESTER symbol defined is not checked, Play in Editor will not start the instrumented app in the Unity Editor.

Workaround: Check the Keep ALTTESTER symbol defined box. Note that this problem does not occur when building an instrumented app for different platforms, only in the Editor.

Affects: AltTester® Unity SDK v1.8.*, AltTester® Unity SDK v2.0.0

Opening AltTester® Editor throws IndexOutOfRangeException: Index was outside the bounds of the array

Problem: Sometimes when opening the AltTester® Editor window IndexOutOfRangeException: Index was outside the bounds of the array is thrown.

Workaround: Close and reopen the AltTester® Editor window.

Affects: AltTester® Unity SDK v2.0.0, v2.0.1


Instrumented app with AltTester® Unity SDK stops working in BlueStacks

Workaround: The issue seems to happen because of the communication protocol used inside the AltTester® Unity SDK. There are other alternatives that work with instrumented builds. For Android you can use the Android Emulator inside the Android Studio. For iOS you can use a simulator inside Xcode.

Affects: AltUnity Tester v1.7.*.

Note: In version 2.0.2 this issue has been fixed.

Networking & Connectivity

AltTester® does not support proxy configurations

Problem: At the moment, AltTester® does not have built-in support for proxy configurations. When using AltTester®, the tool does not handle proxy settings, which can cause connectivity issues

Affects: AltUnity Tester v1.7.1, v1.7.2, AltTester® Unity SDK v1.8.*, v2.0.x, v2.x

WegGL app disconnects

Problem The WebGL application disconnects due to WebSocket timeouts occurring over time when no data is transmitted.

Affects: AltTester® Unity SDK v2.x

Impossibility to connect to AltTester® Desktop an IL2CPP instrumented app built with Managed Stripping Level higher than Minimal which throws InvalidCommandException: Unable to find a constructor to use for type AltTester.AltTesterUnitySDK.Driver.Commands.AltGetServerVersionParams. A class should either have a default constructor, one constructor with arguments or a constructor marked with the JsonConstructor attribute

Workaround: Set the Managed Stripping Level setting to Minimal from Player Settings -> Other Settings -> Optimization

Affects: AltTester® Unity SDK v2.x