Able to filter by clicking on the user portrait in the board/backlog

Problem Definition

When using the Jira Software, user want to filter the issue assigned to a particular number of users by clicking on the user's portrait in the board/backlog

Suggested Solution

As a admin and user :

1. I should be able to click on one or many user portrait in the board/backlog to filter on that person.
2. When I clicked on the user icon, it should be marked in the UI (maybe with a blue frame around it) so that I can see what users I am filtering on.
3. I should able to click on a portrait to filter on it, that user marked shall be ADDED to any Quick filters already in effect.
4. I should able to "unclick" a "selected" user thus removing that user from the filter.
5. The Agile board should show the user pictures in the Agile board that works in the same way as in the backlog.