try this and rebuild the game, this will ignore error and let u continue the game in browser
- Open your project in the Unity Editor.
- From the Unity Editor menu, select Edit > Project Settings.
- Under Publishing Settings, set Enable Exceptions to Full Without Stacktrace.
reference:
https://www.reddit.com/r/Unity3D/comments/zscwai/3d_unity_webgl_error_runtimeerr...