Hello @Riddhesh
Is there any way we can check after user has loaded the discover or visualize page, if the selected index pattern needs to be refreshed without comparing the mapping with the cached fields?
Unfortunately there is not. We've discussed this flaw in index patterns as it can be considerably annoying. It's important to find a solution that doesn't negatively impact another set of users.
That said, I wholeheartedly encourage you to work on this and I'd like to see your results. Do not hesitate to reach out to me.