Bug Very sluggish editor after importing an asset

[DUPLICATE THREAD, please delete]. The original one can be found here:
https://forum.unity.com/threads/202...orming-search-through-20000-elements.1270283/
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Hi there,

I'm an asset publisher, I sell several assets in the Asset Store. One of my users recently brought to my attention a very strange behavior when importing one of my assets (which is a physics add-on, so mainly C# scripts).

Immediately after importing the asset (no need to actually play a scene), the editor starts to behave in an unresponsive and sluggish way. Using the editor profiler reveals there's some kind of enumeration over +20000 elements happening every frame, amounting for 50 ms/frame even on empty scenes.



The stack trace is:
- Application.Tick()
- Application.TickGlobalCallbacks()
- EditorAppliaction.Internal_Invoke()
- <Module>.Invoke_void()
- BaseAsyncIEnumerableHandler.OnUpdate()
- BaseAsyncIEnumerableHandler.FetchSome()
- SearchEnumerator.NextItem()

The user has only been able to reproduce this in Unity 2021.2.17f1 and above, I haven't been able to reproduce it in *any* Unity version.

I've instructed the user in question to report this as a bug and send a repro project, but I'd still like to ask here: Any idea what might be causing this? Does anyone have encountered this before?

thanks!