Someone sent me a commit diff url and asked me to test it, what do I do now?

Someone sent me a commit diff url and asked me to test it, what do I do now?  I have done git clone of the master, and i guess I need to download this url and apply it some how?  I have absolutely no idea how to do this.  And after a couple of hours of reading git documentation, I have made zero progress, nothing makes sense at this point.  Can some one please walk me through this step by step?

Hey @dachshund-digital,

Thanks for being here! Sounds like you are being asked to compare the changes. Here is more info about comparing commits across time.

I hope this helps!