If the list of ideas is long enough to fill the current window, new ideas do not appear immediately on creation. You must switch to Tasks and then back to Ideas to force a refresh of the list display.
It's for performance reasons. If there are a lot of tasks/ideas, rendering the whole list will take a significant time and harms UX, hence the trick of lazy loading.
If the list of ideas is long enough to fill the current window, new ideas do not appear immediately on creation. You must switch to Tasks and then back to Ideas to force a refresh of the list display.