Sourcetree GitHub login doesnt work

This is a reminder to my future self because I need to know this like once a year and I always forget the solution.

This is the problem: You are using SourceTree as version control and you want to Push the latest code you worked so hard on to GitHub. But Sourcetree doesn't let you - instead you see a nasty popup telling you to sign in into GitHub. None of the passwords and username work so you start to think you forgot the password. You go to GitHub, logout, and then login again with one of the passwords you tried in Sourcetree. It works perfectly! So why couldn't you log in to GitHub in Sourcetree? God knows... None of the Google answers made you any wiser...  

The solution is to in Sourcetree click on Options, go to the Authentication tab, click on your GitHub account, click on Edit, and then on "Refresh OAuth Token" - and the nasty popup is nowhere to be seen again (until next year when you have the same problem)!