Trigger an action on a multi-user picker "newly added values"

[mlopez-preference]

Hello all,

I have a multi-user picker field called "Followers". When a user is added to this Followers list, I want to automatically add it to the watchers list. I figured out how to do that by triggering the action when the field Followers changes on the smart value {{issue.follwers.name}} .
The problem is that the action applies to all the users in the Followers list every time it triggers. If a user decides to stop watching the issue and later on a new user is added to the Follwers list, all the followers are added to the watchers, and so is the user that decided to stop watching. I need to apply the action only to "newly added users to the follwers list". Is there a way to figure out who these users are using smart values? 

Thanks in advance!

[Darryl Lee · Accepted solution]

While there is a {{changelog}} Smart Value that should be able to show you what you're looking for, it unfortunately only works for summary, issuetype, and status.

There is an open Improvement request for this:

https://codebarrel.atlassian.net/browse/AUT-407

Alas, we cannot vote for those.