Preface
First, I want to state this is an On-Premises deploy of Dynamics 365 Finance and Operations on the latest Service Update available. We have a current ticket open on the issue with Microsoft but are concerned based on past experiences with UI/performance issues that Microsoft will not be able to solve our issue.
Issue
When we do a browser refresh within Dynamics 365 F&O, the navigation on the left-hand side takes 20 seconds to load (screenshot below for clarify on what I am referencing).
Using the built-in browser debugging tools, I can see that the resource that is blocking the request is the "DensityThemeManager.js" which is calling app.css. Once that resource completes loading, the menu navigation on the left-hand side finishes loading. To be clear, this only happens when doing a full browser refresh, navigation and refreshing within the application form works fine.
We have tried restarting AOS nodes, rebooting all the services, checking SQL backend for blocking and feel like we have exhausted all known options to us. Other than the slow loading of this UI element, the performance of the application is good.
Has anyone experienced the same issue or guidance on what to check next?
