Are you a paid Evernote customer? If so, you won't get the offer overlay, so of course no such issue.
The app is crunching in the renderer, this is display logic, most likely due to the overlay component attempting a complete redraw every cycle, which is a symptom of poorly written fontend code that has a cycle of changes triggering infinite re-renders. In React, solutions to this are useMemo, useCallback, and making sure declared dependencies on useEffect etc aren't about to update every render.
I doubt the overlay needs to read much from the local database. It's an offer overlay, it just needs to know my subscription level, and the current set of offers from the service.