When trying my mods on the new experimental build, I noticed, that all my RestCallback classes I have appear in the Leaks printed when the game exists. This seems to be an issue with the vanilla RestCallback and RestContext classes not releasing the callbacks after the response was received. I never keep any refs of the callbacks.
ctx.POST(new LB_WebhookCallback(type, message, description), "", message);
class LB_WebhookCallback : RestCallback {}
causing SCRIPT (E): Leaked 'WebHookCallBack' script instance (1x)!