Security of using Bing key in a Paperspace notebook

Fastbook says to paste my Bing Image Search key into the notebook, but I’m using Paperspace Gradient’s free account and I’m not sure if it’s safe to paste things like keys into the notebook. I’m not able to access the notebook when not logged in, so I think it’s safe, but is there any security issue?

I found that free notebook instances are public by default, but you can change them to private by clicking Share and turning off the Public switch.