Don't immediately clear jump-to-RM after jumping to it

[ara4n]

No description provided.

[ara4n]

<Adrián Pérez>
okay, more users started hitting our testing server today, and many of them have this suggestion: they would like that the top bar with the up-arrow icon and the “Mark all read” option is not dismissed automatically after pressing the up-arrow to go to the first unread message

or, as a second-best option, that it waits a few seconds before disappearing, and if the user scrolls to the bottom again before the timeout, it doesn't disappear
apparently that second option is what Slack does, but many say they would prefer to manually dismiss it, so they can check a bit their messages, maybe decide to switch to another room, and then come back and be able to jump back to the first unread message (e.g. if there's a lot of messages to read)