WebGL - InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable

Hi there,

I want to change the url in the browser, according to several buttonNames, once the buttons are pressed.

I try to change the url via javascript with this javascriptlibrary.

QueryHandler.jslib

 var QueryHandler = {
     GetParam: function(){
     var level = "";
         var queryString = window.location.search.substring(1);
         var params = queryString.split("&");
 
         for (var i=0; i<params.length; i++) {
             var param = params[i].split("=");
             if(param[0] == "level"){ level = param[1]; }
         }
 
         //send string to Unity
         var buffer = _malloc(lengthBytesUTF8(level) + 1);
         writeStringToMemory(level, buffer);
         return buffer;
     }, 
     SetParam: function(param){
         console.log("window.location.search");
         window.location.search = "?level=" + Pointer_stringify(param);
     }
 };
 mergeInto(LibraryManager.library, QueryHandler);
 

On the buttons i have this C# script

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.SceneManagement;
 using System.Runtime.InteropServices;
 
 public class Url_manipulator : MonoBehaviour
 {
     [DllImport("__Internal")]
     private static extern string GetParam();
 
     [DllImport("__Internal")]
     private static extern void SetParam(string str);
 
     public string path;
     // Start is called before the first frame update
     void Start()
     {
         
     }
 
     // Update is called once per frame
     void Update()
     {
         
     }
 
     private void OnMouseDown()
     {
         SetParam(path);
     }
 }

It changes the Url perfectly fine, but the project unfortunatly restarts, so i see the loading screen and everything.

Also theres InvalidStateError in the mozilla console (same behaviour on chrome):

 InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable
 The script from “http://localhost:59540/TemplateData/UnityProgress.javascript” was loaded even though its MIME type (“”) is not a valid JavaScript MIME type.[Learn More] localhost:59540
 The script from “http://localhost:59540/Build/UnityLoader.js” was loaded even though its MIME type (“”) is not a valid JavaScript MIME type.[Learn More] localhost:59540
 Successfully compiled asm.js code (total compilation time 0ms)
 UnityLoader.js
 The script from “http://localhost:59540/TemplateData/responsive.javascript” was loaded even though its MIME type (“”) is not a valid JavaScript MIME type.[Learn More] localhost:59540
 Responsive WebGL Template by SIMMER.io v2019.02.08 responsive.javascript:2:5
 Available at: https://assetstore.unity.com/packages/tools/gui/responsive-webgl-template-117308 for free! responsive.javascript:3:5
 Host your WebGL Game at SIMMER.io for free! responsive.javascript:4:5
 You can reduce your startup time if you configure your web server to host .unityweb files using gzip compression. UnityLoader.js:3:8480
 [UnityCache] 'http://localhost:59540/Build/unity%20test.wasm.framework.unityweb' successfully downloaded and stored in the indexedDB cache UnityLoader.js:4:11214
 [UnityCache] 'http://localhost:59540/Build/unity%20test.wasm.code.unityweb' successfully downloaded and stored in the indexedDB cache UnityLoader.js:4:11214
 [UnityCache] 'http://localhost:59540/Build/unity%20test.data.unityweb' successfully downloaded and stored in the indexedDB cache UnityLoader.js:4:11214
 Loading player data from data.unity3d UnityLoader.js:4:9380
 Initialize engine version: 2018.3.9f1 (947e1ea5aa8d) UnityLoader.js:4:9380
 Creating WebGL 2.0 context. UnityLoader.js:4:9380
 Renderer: Mozilla UnityLoader.js:4:9380
 Vendor:   Mozilla UnityLoader.js:4:9380
 Version:  OpenGL ES 3.0 (WebGL 2.0) UnityLoader.js:4:9380
 GLES:     3 UnityLoader.js:4:9380
  EXT_color_buffer_float GL_EXT_color_buffer_float EXT_texture_filter_anisotropic GL_EXT_texture_filter_anisotropic OES_texture_float_linear GL_OES_texture_float_linear WEBGL_compressed_texture_s3tc GL_WEBGL_compressed_texture_s3tc WEBGL_compressed_texture_s3tc_srgb GL_WEBGL_compressed_texture_s3tc_srgb WEBGL_debug_renderer_info GL_WEBGL_debug_renderer_info WEBGL_debug_shaders GL_WEBGL_debug_shaders WEBGL_lose_context GL_WEBGL_lose_context UnityLoader.js:4:9380
 OPENGL LOG: Creating OpenGL ES 3.0 graphics device ; Context level  <OpenGL ES 3.0> ; Context handle 1 UnityLoader.js:4:9380
 WARNING: Shader Unsupported: 'Standard' - Pass 'META' has no vertex shader
 UnityLoader.js:4:9380
 UnloadTime: 0.000000 ms UnityLoader.js:4:9380
 Use of the motion sensor is deprecated. 9d80b04b-1533-48a2-9bd1-f8f333642324:2:228360
 Use of the orientation sensor is deprecated. 9d80b04b-1533-48a2-9bd1-f8f333642324:2:228360
 
 ​

Maybe someone is realy into this topic and help me ?! :)