Forever stuck on loading a source PDF

Hi there!

Getting an annoying bug. I've added several PDFs to a notebook, but one of them (larger than the others at 47mb) is stuck loading forever.

It's been days, every time I open the notebook it's still there. Possibly because of this, it never starts loading one of the other PDFs I uploaded.

The worst thing is, I see no way to delete it or stop it from trying to load. The three dots appear grey and don't let me click.

Any ideas to solve this?

Thanks!