IL2CPP Adding a KeyValuePair value to the List corrupts that value in the list

[Release]

What happened?

[Message: Preloader] BepInEx 6.0.0-be.688 - Withering Rooms
[Message: Preloader] Built from commit 4901521

Create a KeyValuePair value.
Read its key/value - everything is fine.
Add the value to the List.
Read the value from the list - we get a garbage value in the key/value.

Same thing if you try to change an existing value in the list.

Steps to reproduce

Code:

List<KeyValuePair<int, string>> list = new();

var item = new KeyValuePair<int, string>(0, "First");
list.Add(item);
Debug.Log("Item is: " + item.Key + " - " + item.Value);

item = new KeyValuePair<int, string>(1, "Second");
list.Add(item);
Debug.Log("Item is: " + item.Key + " - " + item.Value);

foreach (KeyValuePair<int, string> keyValue in list)
{
    Debug.Log("KeyValue is: " + keyValue.Key + " - " + keyValue.Value);
}

Result:

Item is: 0 - First
Item is: 1 - Second
KeyValue is: -2110181048 -
KeyValue is: -2110181048 -

BepInEx Distribution

Bleeding Edge from BepisBuilds

Log outputs

No response

Environment

- OS: Windows 11
- BepInEx: BepInEx 6.0.0-be.688
- Game: Withering Rooms