Reproduction steps:
1. Open attached "MyFirstGame.zip" project
2. Open Build Settings
3. Switch Platform to WebGL
-- Observe the crash

Users reproduced this issue with: 2019.3.15f1, 2019.4.0f1, 2019.4.1f1

First lines of the stack trace:
0x00000000623F7A05 (mono-2.0-bdwgc) [c:\build\output\unity-technologies\mono\mono\mini\aot-runtime.c:2507] mono_aot_get_cached_class_info
0x000000006223BD30 (mono-2.0-bdwgc) [c:\build\output\unity-technologies\mono\mono\metadata\class.c:5039] mono_class_init
0x000000006223CB4A (mono-2.0-bdwgc) [c:\build\output\unity-technologies\mono\mono\metadata\class.c:8175] mono_class_is_subclass_of
0x0000000142A01640 (Unity) scripting_class_has_parent
0x0000000140C6D958 (Unity) CanForwardMonoBehaviourDrawGizmo
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