I updated the code to allow drag-and-drop during dev mode and it worked fine...

The only time it crashed is when I drag a file from the Unity Asset Hierachy (bottom panel... whatever it is called)
But when I drag and drop files from outside of Unity (Straight from my desktop for example), it is flawless.
Has not crashed on me yet, and I've dropped hundreds of files

I'm using Unity 2020.1.8f1