For the full context see the Reference
Description
Now I'm noticing an issue with the previews rendering, in both the sidebar and the expanded view. It just spins...
What we know about the bug
We could not reproduce it consistently but it does sometimes fail to load.
Drag and drop also fails to load randomly in courses (ref)
It seems to occur when virtualdom lib is loaded after drag-and-drop javascript is loaded. And this mostly happens when both the js files are cached by the browser. (ref)
Mostly happens in libraries page of Authoring MFE, while loading the same xblock second time (Popup component preview). This time both js files are cached and load at the same time. (ref)
For the full context see the Reference
Description
What we know about the bug