If you have a Personal Microsoft Account that is being used to log in to GitHub.com and you want to link your GitHub account to Microsoft services (OneNote, OneDrive, etc.), you need to link this Personal Microsoft Account to GitHub. This can be achieved using the following steps, which are not well documented on any sites:
1 Log in to your GitHub account using the Microsoft account in the Google Chrome browser.
2 In the same browser session, navigate to login.microsoftonline.com/
3 On the Sign-in page, do not enter your email address. Instead, choose "Sign-in options" and click on it.
4 On the next screen, choose the option "Sign in with GitHub" and click on it.
5 On the next screen, click on "Authorize Microsoft-corp."
6 This will link your Microsoft account with GitHub services, allowing you to log in to GitHub first and then access other Microsoft services (oneNote or associated with your Personal Microsoft Account in the same browser session.
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