I am using SharePoint Online and was referencing the MicrosoftAjax.js file via /_layouts/MicrosoftAjax.js for the past several weeks without issue. A week later and no changes to the system and it is now not working/can't be found when I try to browse to it. Where is MicrosoftAjax.js located within SharePoint Online? I don't want to use the CDN.
I've also noticed that I can open it from an on premises site via /_layouts/MicrosoftAjax.js