G Suite Add-on refusing to connect to drive? How to solve "drive.google.com refused to connect" error?

Question

I am trying to use a G Suite Add-on called YAMM that I regularly use. Recently, I have been encountering an error "drive.google.com refused to connect" often. When I contacted the developer, they say it is Google's problem. How do I get it fixed?

Solution

This happens if you have signed in with multiple gmail accounts in your web browser. To solve this problem as an end user, open an incognito window, sign in with your gmail account used to install the add-on and use the addon - https://formfacade.com/faq/error-drive-google-com-refused-to-connect-fix.html

If you are an addon developer, migrate your addon to v8 engine - https://formfacade.com/faq/drive-google-com-refused-to-connect-error-for-addon-developers.html