I would love to work on this. This seems like an interesting feature but although less intriguing. This would be a necessary action for future updates

Thanks for the suggestion! Looks like #4828 is a related issue, but both would be helpful.

@Sauvikn98 if you are interested in working on this, you can dig into the code, and post a description of your proposed approach once you have an idea of how you would go about it. @chrisbobbe or @gnprice can comment on whether or not this is an approachable first issue.

Okay! Thank you for the response. I will make a detailed proposal of my approach for this issue by the end of the day and post it for a review.

This makes sense to me as an issue for someone to take on.

One detail for the implementation: I think probably the behavior should be that when the user chooses to do this, we should ask the server to apply the change to all the messages in the topic (rather than try to make it only the messages after a certain point.) That's because in this UI flow, there doesn't seem to be a good way to have the user specify what message they'd want the rename to start from.

(If the user does want to move only the messages starting from a given point, then a natural UI for that would start with long-press on that message. Issue #4828 is for offering that option, among others.)

@gnprice would it be best to wait for zulip/zulip#21739 to be completed, or do you think it's OK to pick this up now?

I think it's OK to pick this up for now, and we can just be conservative about when to show the option: for example, only show it when the user is at least an admin. That should cover a good fraction of the times that people want this feature.

Then after zulip/zulip#21739 is done, and/or #3898 , we can adjust the logic so it more precisely shows the option in all the situations where the user has the permissions for it.