Seems you are having custom code deployed. There might be scenarios where you are still referring to login administration in your code which might be throwing exception and failing to load the page correctly.
Go to view source of the page without editor.html and check if you see any exception.
Also, check browser console for any js errors which might be causing because of adding custom code to OOB clientlibs category.
Is the issue happened suddenly or happening while migration/upgrading the code to new version of AEM ? It will be helpful if you can provide background after when the issue is started happening.