The cool SharePoint modern document library page announced as part of Future of SharePoint became available in our Office 365 tenant recently. The new document library page was working fine for most of our users, some users where seeing a blank page when accessing the library. As the users were seeing a plain white page they were not able to accessible.
While trying to find the cause of the issue with the browser developer tools the below error was logged into the console window
AllItems.aspx:10 Uncaught ReferenceError: require is not defined
Looking into the network tab showed that request to the file https://spoprod-a.akamaihd.net/files/odsp-next-prod_ship-2016-07-04_20160711.001/require-951f856e.js failed.
The request failed because the domain spoprod-a.akamaihd.net was blocked in our firewall system. Once we the domain was unblocked in firewall the library page started working correctly.The updated list of end points that a user should be able to connect for working in SharePoint online can be viewed from https://support.office.com/en-us/article/Office-365-URLs-and-IP-address-ranges-8548a211-3fe7-47cb-abb1-355ea5aa88a2?ui=en-US&rs=en-US&ad=US#BKMK_SPO